Hi again Guys :-)

Once again, my '94 Camry scared the bejeezus out of me, by reving out of control. I was driving a mountainous back road and all of a sudden the car was doing 40 mph on it's own. It was ROARING out of control so badly that I had to shut the car off in Drive. I would get out, pull the linkage back to an idle then start the car and, without touching the gas proceed on my way home. This kept up, until I had a very steep incline to go down. I kept the car in low, and kept touching the brakes. Then, I was smelling my brakes, and decided to just stop and, hopefully, someone would come by with some tools! And they did.......

To make a long story short, I got a 10mm wrench and took the cover off the box that (I think) holds the cruise control and throttle cables. It has sand and dirt all over the guides, springs, and throttle cables. I sprayed it with WD40, kept moving them, and it loosened up nicely. Then I drove the rest of the way home w/o incident.

THis morning, I cleaned all the oil and crud out and was going to blast it w/PB spray, and thought I would ask here if perhaps silicone would work better for me. I live on a dirt road, and there is always a lot of sand around that sticks to anything oily. Wouldn't silicone lubricate equally well, w/o the stickiness that all this sand and dirt sticks to????

(Oh, I checked and cleaned the throttle housing with an old toothbrush and carb cleaner too, but it was the cables in the covered box area that was the problem.)

Any thoughts on this would be appreciated :confused:
Jackie

Silicone is just another type of oil. It is silicon-based instead of hydrocarbon-based. Dust will stick to it also. Get an evaporating teflon spray. If it doesn't leave an oily residue, it will be fine. You can also try a graphite lock lubricant.

Don't forget that if the cable is too chewed up, rusted, dinged or whatever, it will never slide freely with a dry lubricant. You will need to get a new cable if you want it to be reliable.

Don't forget that if the cable is too chewed up, rusted, dinged or whatever, it will never slide freely with a dry lubricant. You will need to get a new cable if you want it to be reliable.

Thanks Brian, and the cables themselves looks like new. Bright n' shinny, the whole nine yards!

I will look for that evaporating teflon spray when I go to town. And, why didn't I think of using graphite? We used to use that for everything years ago. Geeeeze!

Also, one thing I did learn through this ordeal; I will always carry a cheap set of tools in this car from now on. AND, some spray lubricant! But then again, you can practically rebuild this car with just a 10 and 12mm wrench! LOL!!! Thanks again Brian :biggrin:

Jackie (with a few more gray hairs now)

GRRRRRRRRRRRRRRRRRRRRRRRR!!!! This throttle sticking deal is going to get me killed! I took the car to town after spraying the heck out of it will PB spray, and the throttle stuck again!!!! I sprayed the cables and springs near the throttle body, in the box that houses the cruise control, and cleaned out the throttle body AGAIN with carb cleaner. What else can I do here? I did notice that it seems to be hanging up at the first (closest to firewall) lever in the cruise control box. The cable moves freely, but the spring loaded arc type lever doesn't take up the slack in the cable when it sticks. And, when I spray the crap out of it, it seems to be fine again for another 100 miles or so.

Does anyone have an idea what else I can do to keep this from happening again????

Jackie

It is possible that there is dirt and crud inside the cruise control actuator. You don't mention if this happens when the cruise control is on or off, but the throttle and cruise control are mechanically linked through that actuator. If it is sticking, then it ought to be replaced...I do not know if the unit can be opened for repair or cleaning.

Does the CRUISE light on your instrument panel flash when you turn it on? If so, there is a trouble code stored in the ECU. Download the Body Electrical System service manual stickied at the top (BE) and read the code (page BE-168).

Another but less likely possibility is that the little magnetic clutch that engages the cruise control is not disengaging or has a short circuit. This may also require replacement of the actuator.

Perhaps you can disconnect the cable from the actuator to the throttle to prevent this until you can look at it?

It is possible that there is dirt and crud inside the cruise control actuator. You don't mention if this happens when the cruise control is on or off, but the throttle and cruise control are mechanically linked through that actuator. If it is sticking, then it ought to be replaced...I do not know if the unit can be opened for repair or cleaning.

Does the CRUISE light on your instrument panel flash when you turn it on? If so, there is a trouble code stored in the ECU. Download the Body Electrical System service manual stickied at the top (BE) and read the code (page BE-168).

Another but less likely possibility is that the little magnetic clutch that engages the cruise control is not disengaging or has a short circuit. This may also require replacement of the actuator.

Perhaps you can disconnect the cable from the actuator to the throttle to prevent this until you can look at it?

I just drove the car about 80 miles and it behaved perfectly. No, I wasn't using the cruise when the problem occurred. When I do use the cruise, the light comes on steadily as it should (?) it does not blink. I did consider removing the actuator arm from the cruise to the throttle, and now I will.... just to see if it happens with it disconnected.

Is there anything else electrical that can be making this happen? Or, perhaps a sensor? It surely seems to be more of a mechanical thing to me though. I mean, it sticks, I spray, and it's fixed. WEIRD, huh? :banghead:

Thanks for your suggestions, and I'll let you know how I make out with it :-)
Jackie

The throttle was sticking on my 1997 Camry LE becuse the TB was full of gunk. When we were at a stop, the throttle would be hard to press, but then release, launching the car forward. Maybe the same this is happening here wher the throttle butterfly valve is being stuck in the open. Take the freash air intake off the TB and open the valve ... If it's pretty dirty in there, that could be it. You'll have to take the TB off and clean it with a scotch pad and carb cleaner. That's what I ended up doing and it fixed it.

Let us know how you do .... Paul - Dunstable, MA

I agree with pcushion that it's likely to be a sticking throttle valve inside the throttle body. If you didn't clean that before, do it now. There are 2 corrections I would like to make about cleaning it. First, it is not necessary to take the throttle body off the car to clean it. It can be cleaned right on the car and with the engine off. Second, do not use a scotch pad on it. That is simply too harsh and may scratch the area where the throttle valve seats, when it's in it's idle position. All you need is some spray throttle body cleaner or some O2 safe carb cleaner, along with a rag or a toothbrush for really stubborn buildup. Make sure you clean both the front and backside of the throttle valve along with the area around where it seats when it comes back to it's idle postion. Have someone hold the gas pedal to the floor (engine still off) to expose the backside of the throttle valve. If you are not familiar with how to clean it do a search. It has been covered numerous times.

Mike

Thanks for the replies Guys.. but........

I cleaned the throttle body with carb spray when I lubricated all the cables.


Since the car performed beautifully yesterday, I took it for a drive about 35 miles, and guess what???? Yep, the damn thing stuck again!!!! I got out, pushed the accelerator lever back doan, sprayed it, and brought the car home. It behaved well on the way home!!!!

When I got home, I cleaned the throttle body again with carb spray and a soft toothbrush.....just in case I missed something before.
I then took the cables off and sprayed them liberally with PB spray. They are working smoothly with no sticking. I had someone keep pressing the gas pedal as it they were driving in traffic and as if on the open road. It never hung up once. In the area of the cruise control and lever type things, there is a spring. Should there be resistance on this lever that the cable fits into. This is hard to explain......please see picture at bottom of post... see the spring? It doesn't do anything!!!!!!!! Should it? (The bottom of the picture is the front of the car.) Oh, and the car has 149,100 miles.

Is is possible that there is some other reason that this is revving up? Computer.... Throttle positioning Sensor?? This is C R A Z Y!!!!

http://i5.photobucket.com/albums/y191/AdkGal/P1070663.jpg

No one has an answer about the spring on this lever in the cruise control area? C'mon guys, if I don't get help here, I have to take it to a mechanic, and I don't have the $ for that.....

H E L P!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Jackie

Contrary to popular belief, some of us gearheads DO remove our heads from under the hoods once in a while. And it is summertime, when vacations abound. I can understand your frustration at this, but diagnosis is much more difficult when we are limited to pics and typing versus real-time touch-and-feel. I simply haven't had time to pull the cover off and look at my set-up.

Honestly, the cruise control on the Camrys isn't one of the more trouble-prone systems, so the slow response kind of justifies that...we're just not that familiar with it. Bear with us. The spring does do SOMETHING, we just don't know yet. :uhoh: It appears to provide a resistance for the cruise control to measure the actual throttle position versus what the CC is requesting. OR it could be a CC throttle damper to smooth out small throttle changes....

Question #1: When it got stuck again and you said you pushed the accelerator lever down...do you mean the one on the TB or on the cruise control system? Sometimes you can feel it unsticking when you turn it or you can see the cable slacken when you turn one and it causes the other to unstick.

Question #2: Does the accelerator usually get stuck in the same position every time? 1/2 throttle? Wide-open throttle? Or does it vary?

I'd hate to suggest it, but frankly if all this spraying and brushing isn't cleaning out the crud that is causing it to stick, then I'd suspect that the TB needs to be disassembled and inspected for scoring where the butterfly valve shaft connects to the TB and/ or the cruise control actuator needs to be replaced. The only other thing I can think of is that the PB or whatever you are using is actually causing the sticking by gumming up and hardening as the engine heats up. Those lubricants are very low viscosity and will evaporate quickly when heated, leaving behind whatever else is in the oil formula as a gummy or solid residue.

Contrary to popular belief, some of us gearheads DO remove our heads from under the hoods once in a while. And it is summertime, when vacations abound. I can understand your frustration at this, but diagnosis is much more difficult when we are limited to pics and typing versus real-time touch-and-feel. I simply haven't had time to pull the cover off and look at my set-up.

Honestly, the cruise control on the Camrys isn't one of the more trouble-prone systems, so the slow response kind of justifies that...we're just not that familiar with it. Bear with us. The spring does do SOMETHING, we just don't know yet. :uhoh: It appears to provide a resistance for the cruise control to measure the actual throttle position versus what the CC is requesting. OR it could be a CC throttle damper to smooth out small throttle changes....

Question #1: When it got stuck again and you said you pushed the accelerator lever down...do you mean the one on the TB or on the cruise control system? Sometimes you can feel it unsticking when you turn it or you can see the cable slacken when you turn one and it causes the other to unstick.

Question #2: Does the accelerator usually get stuck in the same position every time? 1/2 throttle? Wide-open throttle? Or does it vary?

I'd hate to suggest it, but frankly if all this spraying and brushing isn't cleaning out the crud that is causing it to stick, then I'd suspect that the TB needs to be disassembled and inspected for scoring where the butterfly valve shaft connects to the TB and/ or the cruise control actuator needs to be replaced. The only other thing I can think of is that the PB or whatever you are using is actually causing the sticking by gumming up and hardening as the engine heats up. Those lubricants are very low viscosity and will evaporate quickly when heated, leaving behind whatever else is in the oil formula as a gummy or solid residue.

Answer to #1: When it stuck again, I pushed the lever down at the TB. When I push it down, it feels quite stiff.

Answer to #2: I would say it sticks at approx 1/3 throttle. When I am driving, and the tranny upshifts, it feels like full throttle, but that is only because I am in a higher gear. However, the 1st time it stuck, I gave the gas pedal a quick shot, and the rpms soared and stayed... I had to shut the car off!

There can't possibly be any crud left at either levers. I used a degreaser, a brush, and a jet spray of hot water to clean them.

I'm thinking you may be right about the TB having to be taken apart. Even though I have cleaned it numerous time, I may be missing something. It looks very clean, and feels very smooth, and I feel no grooves or scoring when I run my fingernail across the inside ot the TB. But, something certainly isn't right!

Sorry if I have come off as impatient or possibly demanding. But, I am just soooooo frustrated. I cannot/will not drive the car any more. It's just too dangerous like this. :banghead:

I spoke with a mechanic, and he wants me to make an appt so he can use his test computer to diagnose the problem. He seems to think it's a computer or sensor problem. Is that possible?????

Thanks for your help and any more suggestions you may have.
Jackie

Sorry if I have come off as impatient or possibly demanding. But, I am just soooooo frustrated. I cannot/will not drive the car any more. It's just too dangerous like this. :banghead:

Don't worry about that ... We've all been there more times than not.

I spoke with a mechanic, and he wants me to make an appt so he can use his test computer to diagnose the problem. He seems to think it's a computer or sensor problem. Is that possible?????

He could be right ... It could be a throttle position sensor ... It seems that you have done everything a driveway mechanic could do. Good luck and keep us informed.

I'll stick with my diagnosis of a sticking TB...something somewhere in there, since you confirm that it is physically stuck. The TPS can only indirectly control it via vacuum. But I will concede that the TPS is a possiblity, too. I will note that hot water is not necessary to clean off the TB, and may cause corrosion formation where dissimilar metals are in contact. It doesn't take much to cause binding. Hopefully, the water wash was followed up by a shot of carb cleaner.

My only other revelation would be to check the throttle cable between the pedal and TB. It may have gunk in it too, have a kink, or need lubrication. Does the pedal stick too when it gest stuck or does it spring back when you lift off?

No worries about being frustrated, especially when safety comes into question. Hopefully, we'll find the problem!:grinyes:

Just read in the factory repair manual to not clean the TPS with carb cleaner as it may cause deterioration. Granted your problem started before you used it, but I'm wondering if the problem may have been exacerbated.

I'll stick with my diagnosis of a sticking TB...something somewhere in there, since you confirm that it is physically stuck. The TPS can only indirectly control it via vacuum. But I will concede that the TPS is a possiblity, too. I will note that hot water is not necessary to clean off the TB, and may cause corrosion formation where dissimilar metals are in contact. It doesn't take much to cause binding. Hopefully, the water wash was followed up by a shot of carb cleaner.

My only other revelation would be to check the throttle cable between the pedal and TB. It may have gunk in it too, have a kink, or need lubrication. Does the pedal stick too when it gest stuck or does it spring back when you lift off?

No worries about being frustrated, especially when safety comes into question. Hopefully, we'll find the problem!:grinyes:

Okay guys......

Here's the deal..... You all kept saying clean the TB, and I kept saying that I did clean it, in fact, MANY TIMES! Well, I decided today to take the TB off the car and take a look inside! Do I hear you all gasping? LOL! Well, I was going along fine getting the TB off until I hit a stumbling block. There were 2 hoses attached to the bottom and I couldn't get them off. However, I could get a good look at the inside/backside of the TB and I was shocked at what I found. Especially since I was so careful cleaning it. So, I would suggest anyone cleaning their TB should take it off to make sure BOTH sides are clean. Check this out!:


http://i5.photobucket.com/albums/y191/AdkGal/TBbefore.jpg

So, very carefully I cleaned the back side too, and now it looks like this:



http://i5.photobucket.com/albums/y191/AdkGal/TBafter.jpg
So, Lets hope this problem is solved. I'll know better after the car is driven for a few miles. I will, however, stay out of high traffic areas and stick to the back roads for a while. LOL!

I would like to thank everyone who helped me with this problem.... lets just hope that is is solved!

You guys ROCK!!!!!:smooch:

Jackie

I'll stick with my diagnosis of a sticking TB...something somewhere in there, since you confirm that it is physically stuck. The TPS can only indirectly control it via vacuum. But I will concede that the TPS is a possiblity, too. I will note that hot water is not necessary to clean off the TB, and may cause corrosion formation where dissimilar metals are in contact. It doesn't take much to cause binding. Hopefully, the water wash was followed up by a shot of carb cleaner.

My only other revelation would be to check the throttle cable between the pedal and TB. It may have gunk in it too, have a kink, or need lubrication. Does the pedal stick too when it gest stuck or does it spring back when you lift off?

No worries about being frustrated, especially when safety comes into question. Hopefully, we'll find the problem!:grinyes:

Okay guys......

Here's the deal..... You all kept saying clean the TB, and I kept saying that did did clean it, in fact, MANY TIMES! Well, I decided today to take the TB off the car and take a look inside! Do I hear you all gasping? LOL! Well, I was going along fine getting the TB off until I hit a stumbling block. There were 2 hoses attached to the bottom and I couldn't get them off. However, I could get a good look at the inside/backside of the TB and I was shocked at what I found. Especially since I was so careful cleaning it. So, I would suggest anyone cleaning their TB should take it off to make sure BOTH sides are clean. Check this out!:


http://i5.photobucket.com/albums/y191/AdkGal/TBbefore.jpg

So, very carefully I cleaned the back side too, and now it looks like this:



http://i5.photobucket.com/albums/y191/AdkGal/TBafter.jpg
So, Lets hope this problem is solved. I'll know better after the car is driven for a few miles. I will, however, stay out of high traffic areas and stick to the back roads for a while.

I would like to thank everyone who helped me with this problem.... lets just hope that is is solved!

Jackie

Well it appears cleaner now, though I'll have to ask if you rotated the butterfly disc open and cleaned the edge and mating surface. That edge right where the disc and TB throat mate at either end of the valve shaft is where the sticking occurs (you can see where there is some darker discoloration on the throat around the shaft ends).

I would also be very careful to not use abrasive cleaners. Too much abrasion can cause unwanted gaps, preventing the butterfly valve from making a proper seal.

Excellent pics!

In the future you can get to the back side of the throttle valve inside the throttle body without taking the throttle body off. Just have someone inside the car hold their foot on the accelerator, holding in firmly on the floor. This will cause the throttle valve to become horizontal and expose the back side for easy cleaning. If you dont have a second person to help you you can also open it manually using the linkage attached to it and then jam a screwdriver in the linkage to keep it open. This is what I do to clean both sides without removing it.

Mike

Well it appears cleaner now, though I'll have to ask if you rotated the butterfly disc open and cleaned the edge and mating surface. That edge right where the disc and TB throat mate at either end of the valve shaft is where the sticking occurs (you can see where there is some darker discoloration on the throat around the shaft ends).

I would also be very careful to not use abrasive cleaners. Too much abrasion can cause unwanted gaps, preventing the butterfly valve from making a proper seal.

Excellent pics!

Yes, I did rotate the butterfly plate to get all the edges. (I hope I got them! LOL!) Anyway, I have no idea what that discoloration is at each end of the butterfly. Looks like something from the manufacturer.

I was very careful cleaning it. I used a soft toothbrush and carb cleaner. I read somewhere where a guy used a wire brush!!! YIKES!!!!! I still say, taking it apart is the only way you can be absolutely sure you got all the crud out.

Thanks! I took the pictures because I was shocked at all the crud I missed when I cleaned it all those other times. I just wanted to share the shock, I guess! LOL

Jackie

I have a 1989 Camry 5 speed...yeah it was revving like crazy on me..every time I got to a light, the car next to me thought I wanted to race!

Took it to the local mechanic, he said it was the Idle Speed Control
I could get one cheaper online than he was gonna rook me for, but then he said he wouldn't install the part if I got it...so off to another mechanic I went

Guess what, this guy had seen this before, on a fluke, and knew exactly what was wrong! It wasn't the ISC...

It was a TEMP SENSOR! the car keeps thinking it is cold, so it increases the idle to warm itself up. Mine is fixed and runs like a top! 256K miles...Maybe what yer problem is...

Well guys.......

Since I posted the last time, I purchased some liquid graphite spray from NAPA ($9 a can!) and sprayed the crap out of all the cables and levers associated with the throttle. I took it for a ride. No problems........

Then, today. I had to drive it to town, a distance of 35 miles, and it was perfect. I went to the store, started the car, put it in gear.. and guess what?????? IT STUCK AGAIN!!!! (Yes, I Am screaming!) I slid the car into neutral and it wasn't revving too badly (approx 2000 rpm) so I put it in park and opened the hood. I sprayed everything to see if I could make it come down w/o physically pushing it back down, but the spray didn't work. I pushed the throttle lever back down and drove the car home w/o incident.

HHmmmmm.... I thought about every time it stuck on the way home, and it was always after driving and shutting the car off for a little while. Perhaps "LyricLover" has the answer with this temperature sensor thing??????

If I can figure out which sensor is the temp sensor, and I unplug it when the throttle revs, will it go back to an idle? Does that make sense? I guess I am trying to isolate the problem so I don't have to replace it needlessly. This could get expensive, huh?

Any input is appreciated :shakehead
jackie

HHmmmmm.... I thought about every time it stuck on the way home, and it was always after driving and shutting the car off for a little while. Perhaps "LyricLover" has the answer with this temperature sensor thing??????


I would say it's not an issue with the temperature sensor since you said you had to manually push the throttle lever back down. your throttle is still sticking for whatever reason.:banghead:

Regards,
JOET/CAMRY

What would a new OEM throttle cable set you back? I going to suggest replacing the cable from the pedal all the way to throttle body.

Besides I wanted my third star.

Besides I wanted my third star.


HAHAHAHAHAHA!!!! Okay, you now have THREE gold stars! Congratulations!

I don't know how much an OEM set of cables would cost and would be afraid to ask! Besides, the cables move like soup through a goose, if you get my drift! LMAO!

Enjoy your new star! hahahahaha :rofl:
jackie

As much a PITA it would be to install it, about 1/3 as much as the labor...if you could even find a new one.

3 stars...been there, flubbed that.

Yesterday, I once again loosened the throttle body so I could see the back side. (The reason I didn't take it completely off the car is.... I cannot get one of the the coolant hoses off the bottom of it.) Anyway.... the throttle body is as clean as the day the car was manufactured so it's NOT the problem. It was suggested that I lube the TB shaft, so I carefully placed a small drop of PB spray at the tiny slot where the TB plate is on the shaft as it goes into the TB, then opened and closed the valve to distribute it, then wiped the TB clean.

The cables themselves, slide VERY smoothly, and I also lubricated them with wet graphite while I had them off. The area that I just don't understand is the cruise control levers and springs. There are two levers; each with a spring, but they just don't seem to have a lot of resistance when I move them. Also, when I move the throttle as though I was pressing down on the accelerator, the top cable on the TB isn't taken up by the forward lever thing in the cruise control box very well. But, when the cable is disconnected, the cable moves very well.

Any ideas? I have to use the car today, so I will post again if it misbehaves again. I will say one thing though..... when the accelerator stuck this last time, it was at a much lower rpm.

Any comments would be appreciated.
Jackie

Well, the 30 mile trip was perfect. I parked the car and went into the store. Approximately 10 minutes later I started the car, and it idled well. I put the car into drive and touched the accelerator and it stuck again! I put the car in park and it was idling about 2200 rpm. I opened the hood, pulled the cable driven lever on the cruise down to an idle, and it felt as though it was stiff. Unless it was my imagination. The car ran perfectly on the way home, and the throttle did not stick again.

Well.... if anyone has a clue what is going on, please enlighten me :shakehead

Jackie

When you say "stick" is the throttle staying where you command after you release pressure on the pedal or is it driving past where you command it and staying there? Might be a tough one to determine. Have you duplicated it in your driveway?

Okay, I went under the hood and examined my setup and here's what I think could be the culprit...a sticking or broken IAC Idle Air Control valve. It is a little plunger that sits under the TB and is fed by a short vacuum tube that runs from the top of TB (a tube separate from the other three...between them and the TB spring) to a ~1-1/2" diameter diaphragm.

When the engine is shut off, vacuum dissipates and spring-loaded plunger pushes the TB open a little. When the engine is restarted, the plunger should pull back in once vacuum is restored. It moves abt 1/2". You can test the valve by pulling the vacuum tube off the TB...it should push out and raise the idle speed to ~1500 rpm. If you try to turn the TB shaft assembly back to normal idle, it should be very hard to turn but not impossible. Pushing the vacuum tube back onto the TB connection should retract the plunger. If not, it is sticking or broken and should be replaced.

On my engine, there is abt a 1/4" gap between the plunger piece and the tang that it pushes against to rotate the TB shaft...if yours is smaller or none, then that may be the reason it is revving around 2000 instead of my 1500 rpm. There's a little adjusting bolt you can turn to increase that gap. good luck!

When you say "stick" is the throttle staying where you command after you release pressure on the pedal or is it driving past where you command it and staying there? Might be a tough one to determine. Have you duplicated it in your driveway?

The first time it happened, the car built speed. In fact, the car accelerated to about 40 mph going up a steep hill! (It accelerated to 40 mph on it's own without me touching the gas!) However, lately, it seems to be going to about 2000 to 2200 rpms and staying there. ( Staying where I commanded it. ) I have tried many times to duplicate it at home without success.

Thanks,
Jackie

Okay, I went under the hood and examined my setup and here's what I think could be the culprit...a sticking or broken IAC Idle Air Control valve. It is a little plunger that sits under the TB and is fed by a short vacuum tube that runs from the top of TB (a tube separate from the other three...between them and the TB spring) to a ~1-1/2" diameter diaphragm.

When the engine is shut off, vacuum dissipates and spring-loaded plunger pushes the TB open a little. When the engine is restarted, the plunger should pull back in once vacuum is restored. It moves abt 1/2". You can test the valve by pulling the vacuum tube off the TB...it should push out and raise the idle speed to ~1500 rpm. If you try to turn the TB shaft assembly back to normal idle, it should be very hard to turn but not impossible. Pushing the vacuum tube back onto the TB connection should retract the plunger. If not, it is sticking or broken and should be replaced.

On my engine, there is abt a 1/4" gap between the plunger piece and the tang that it pushes against to rotate the TB shaft...if yours is smaller or none, then that may be the reason it is revving around 2000 instead of my 1500 rpm. There's a little adjusting bolt you can turn to increase that gap. good luck!

THANKS!!!! I wondered about that thing (IAC), but had no clue how it was supposed to work. I will definitely do the test that you suggest tomorrow and post my results.

Jackie

Oops, the part I'm referring to is not the IAC valve, but simply the throttle opener. The IAC valve is underneath the TB, just to the right of the throttle opener. Sorry for any confusion.

The first time it happened, the car built speed. In fact, the car accelerated to about 40 mph going up a steep hill! (It accelerated to 40 mph on it's own without me touching the gas!) However, lately, it seems to be going to about 2000 to 2200 rpms and staying there. ( Staying where I commanded it. ) I have tried many times to duplicate it at home without success.

Thanks,
Jackie

What I was getting at was I'm wondering if instead of "sticking" could something be driving the throttle and or throttle cable and holding it there. The only thing I can see that may "drive" the cable is the cruise control unit. Might try pulling the fuse and disconnecting and plugging the vacuum hose to it. The only other unit I can think of with a direct input based on throttle position is the Throttle Position Sensor or TPS. I believe it is mechanically connected to the throttle plate shaft. I can't picture the TPS "driving" the throttle though.

The IAC is a motor driven valve positioned by inputs from the PCM. It opens a small hole behind the throttle plate in the throttle body to allow air to bypass the throttle plate anytime the plate is closed to maintain idle rpm. Amongst other modes it is what boosts the idle rpm when you turn on the A/C. It isn't connected to the throttle plate shaft.

The TPS could itself be sticking, causing the throttle plate to bind. The CC isn't vacuum driven. But it can be disabled by disconnecting the wiring connector on the front of the unit...or pull the fuse. The CC is a servo motor that moves a third lever to mate with the second lever on the CC's throttle cable assy. I did notice that I have a good sized gap (~1/4" or more) between this third lever and the part it contacts on the second lever, whereas your pic doesn't show any gap. Perhaps the CC's servo isn't retracting all the way? Also, there is a spring return on the servo lever...if that is broken or weak, it may also prevent full disengagement. Push it towards the firewall and make sure it returns to the off position and does allows the TB cable lever to also return to idle. There's a little adjusting bolt to change the gap...I would say at least 1/16" to ensure complete disengagement. The factory manuals don't state a spec for it that I could find.

Sorry to take so long in replying to all your suggestions to my problem, but family matters needed my attention these last few weeks. :uhoh:

Now, jdmccright: I checked out the throttle opener and it is working properly.

RIP: I took everything in the CC area apart and cleaned it. Everything including the levers are now working smoothly as I think they should.

I did some detective work today. I got out the Haynes book and checked out the diagnostics. I have a code 22 which is a coolant sensor malfunction. However, when I test the sensor itself, it checks out fine both hot and cold, and the circuit has the proper voltage.

Anyone have a sure-fire way to tell if this is the coolant sensor causing my fast idle???? (I remember "LyricLover mentioned this was the problem with his camry?)

Thanks again guys!
Jackie

A code 22 means: "Open or short in the coolant sensor temperature sensor circuit." Key word there is circuit. The ECT circuit consists of the sensor, the ECM, and the wiring between. I would agree that 80% of the time the sensor is bad. I'd bet 19 of the remaining 20% it's a problem with the wire harness. You need to take some time and visually inspect the wire harness from the sensor to the ECM. At least where it's accessable. Look for any indications of chaffing/bare wire/corrosion/arcing. Make sure the connections look good. If that checks out ok, I would bite the bullet and change the sensor. No guarantees but, if you change it and still have the problem, at least you've eliminated the sensor.

After scratchin the bean I came up with disconnecting the sensor when you have the high idle. Not sure what should happen but try it and come back with the results. Maybe we can figure something out from there.

Ayup, the coolant temp sensor was mentioned before, but the Code 22 is the first time you've mentioned that in all this. This is a code which would illuminate the CEL. Or the bulb was burned out or missing....who knows?

According to the FSM (pg. EG1-356):

"When the resistance value of the engine coolant temperature sensor changes in accordance with changes in the engine coolant temperature, the potential at the terminal THW also changes. Based on this signal, the ECM increases the fuel injection volume to improve driveability during cold engine operation. If the ECM detects the diagnostic trouble code 22, it operates the fail safe function in which the engine coolant temperature is assumed to be 80°C (176°F)."

This fail-safe condition is not really a cold condition...actually abt 20°F below normal op temp for the thermostat. I wouldn't expect the ECM to feed that much more fuel to compensate for a minor drop in engine temp...I'd expect it to hover in the 1200 rpm range...2000 as you mentioned before is significantly more throttle.

I'd suggest clearing the trouble code, then try to replicate the cause standing still...engine at normal temp, then stop & shut it off...now disconnect the cable from the CC to the TB but don't let the cable itself move...wait 10 minutes...open the hood, have a friend restart and give it a little gas by turning the TB valve with your hand, blipping the throttle a little more each time until you get it to that rpm area. If it still sticks, it's the TB and/or the return spring. If not, I'd say the CC-TB cable is binding up just enough to prevent the TB return spring from working.

All the same, if the CEL light comes back on then it's a circuit problem.

Boy, what a stumper....

Make sure the connections look good. If that checks out ok, I would bite the bullet and change the sensor. No guarantees but, if you change it and still have the problem, at least you've eliminated the sensor.

After scratchin the bean I came up with disconnecting the sensor when you have the high idle. Not sure what should happen but try it and come back with the results. Maybe we can figure something out from there.

Well RIP, I went to town today and took a bite of that bullet.. I bought a coolant temp sensor. I will check out all the wiring and if everything looks okay, I will install the sensor if only to eliminate it as a cause of the problem.

re: unplugging the sensor... I'm thinking the car will stall, because I tried to start the car with it unplugged and it wouldn't start. But... I will give it a go tomorrow just to see........

Stay tuned!!!!!
Jackie

Ayup, the coolant temp sensor was mentioned before, but the Code 22 is the first time you've mentioned that in all this. This is a code which would illuminate the CEL. Or the bulb was burned out or missing....who knows?


I'd suggest clearing the trouble code, then try to replicate the cause standing still...engine at normal temp, then stop & shut it off...now disconnect the cable from the CC to the TB but don't let the cable itself move...wait 10 minutes...open the hood, have a friend restart and give it a little gas by turning the TB valve with your hand, blipping the throttle a little more each time until you get it to that rpm area. If it still sticks, it's the TB and/or the return spring. If not, I'd say the CC-TB cable is binding up just enough to prevent the TB return spring from working.

All the same, if the CEL light comes back on then it's a circuit problem.

Boy, what a stumper....

Yes, this certainly IS a stumper! LOL!!!!

I never mentioned the code 22 before, because I didn't know I had it. Perhaps my CEL isn't working properly? Who knows! GGgggrrrr!!!! Anyway, I used the jumper technique as in the Haynes repair manual and found this code 22. Also, I tried to erase it as mentioned in the book as well, but the code keeps coming back.... It likle a bad dream,,, it's always there! LMAO!

re: trying to duplicate the problem..... I can do all of that, but how can I disconnect the cable from the CC to the TB w/o moving it? Or, am I not understanding what you want me to do? Maybe it will make more sense how to do it when I am looking at the cable?????? I'll know more tomorrow, and will update this post then for both you guys that are trying to help.

I APPRECIATE you guys soooooo much for your help!
Jackie

You can unhook the TB cable end by turning the TB shaft assy clockwise all the way open while holding the cable (you mentioned before that it goes slack), after the engine is off. Try to do this before you change out the sensor.

We're not as good as hands-on mechs, but we try.

Wow a lot of verbiage!
Look, if it is physically stuck with all external linkage disconnected then it is in the throttle body.
No need to figure out why, just get another one!
A wrecking yard is a little expensive but you have a 30 day guarantee and you get to look and play with it.
Not a sensor, not electrical, it is binding physically. Sounds like you do have a problem with at least one sensor/circuit but it is not causing the physical binding.
Concentrate on the shaft and its condition, from the pictures I see, it is suspect already. There is plating delaminating on the butterfly and shaft both. If there is any play in the shaft to body bearing that can also cause it to bind as dirt and that black gunk you showed in the first pictures has filled in the void in the bearing and then if the shaft is slid sideways it now tightens were there isn’t worn surfaces.
Carb cleaner and toothbrush, NOT GOOD! The carb cleaner will dissolve the plastic and that plastic film will coat everything. Shouldn’t need to brush at all, just let the chemicals clean it. Or a fine brass brush will work.
For the same reason some of the non-metal throttle body components CAN NOT have carb cleaner on them as well.

Don’t get too far from the basics on this.

Wow a lot of verbiage!
Look, if it is physically stuck with all external linkage disconnected then it is in the throttle body.
No need to figure out why, just get another one!
A wrecking yard is a little expensive but you have a 30 day guarantee and you get to look and play with it.
Not a sensor, not electrical, it is binding physically. Sounds like you do have a problem with at least one sensor/circuit but it is not causing the physical binding.
Concentrate on the shaft and its condition, from the pictures I see, it is suspect already. There is plating delaminating on the butterfly and shaft both. If there is any play in the shaft to body bearing that can also cause it to bind as dirt and that black gunk you showed in the first pictures has filled in the void in the bearing and then if the shaft is slid sideways it now tightens were there isn’t worn surfaces.
Carb cleaner and toothbrush, NOT GOOD! The carb cleaner will dissolve the plastic and that plastic film will coat everything. Shouldn’t need to brush at all, just let the chemicals clean it. Or a fine brass brush will work.
For the same reason some of the non-metal throttle body components CAN NOT have carb cleaner on them as well.

Don’t get too far from the basics on this.

4Wheel......
Yes, this is a lot of verbiage (new word?) However, the guys on this forum are trying to troubleshoot a difficult problem w/o seeing the car. So, much explaining is necessary.

#1. I don't want another throttle body out of a junk yard. My car only has 149k and most of the cars in a junk yard are "junk" or they wouldn't be there.
There is no delaminating of any part of this throttle body. Besides, how can a brass plate delaminate? Also, I have never been able to make the TB stick intentionally... with or without the cables connected...In other words, I cannot replicate the problem.

#2. I agree with you about the toothbrush and carb cleaner. It makes a lot of sense, and now I'm sorry I used the brush. However, with all the spraying I did after the brush, I can only hope that any plastic residue was washed away.

#3. Yes, I did have a sensor problem. Today I replaced the coolant temperature sensor, and the code 22 was cleared and did not return after driving the car 20+ miles, nor did the car rev up. <<<<fingers crossed>>>>

#4. I'm beginning to believe that I had two separate problems. One being the build up of crud in the TB, and the second being the coolant temp sensor. If you read the entire thread, you would have seen that in the beginning the car revved so high that I couldn't put it into park or neutral. Then, after the cleaning of the TB, it only seemed to rev to 2000 rpms or so, and only after being driven and shut off for a short time, then restarted.

Thanks,
Jackie

You can unhook the TB cable end by turning the TB shaft assy clockwise all the way open while holding the cable (you mentioned before that it goes slack), after the engine is off. Try to do this before you change out the sensor.

We're not as good as hands-on mechs, but we try.

Jdm.....sorry, I replaced the sensor before I read this post.:frown:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Jdmccright & RIP...

I feel as though I owe you both an explanation of my CEL thing.....

First of all, my CEL never came on, and I wouldn't have known about the code 22 if I hadn't found the way to diagnose the system with the help of a Haynes manual. An interesting point here; when I had the code 22 blinking in the CEL, my "Overdrive Off" light was flashing as well. It wasn't flashing to the same beat as the CEL, it had it's own tempo and flashed a 36!!!!
Is my car possessed? hahahahaha!!!!

Okay, now the coolant temperature sensor is replaced, and the code 22 erased from the computer. I took the car for a 20+ mile drive and it performed flawlessly. I got home, allowed the car to sit for 15 minutes and restarted it. The idle was good.

It's possible that I had 2 problems. In the beginning, it may have been the crud in the TB because it more or less ran away with me like it had a mind of it's own. But, the later problem was only a slightly elevated rpm (at least compared to doing 40 mph on it's own up a mountain!)

Still, I have to agree.... even when it has been 40 below zero, I have never had the car idle at 2000 rpm's as it did the other day. But again, looking back, it seemed like two different problems... 1, the car revved out of control, I would push the linkage back to an idle, but it kept going back up. Then, this second problem of a slightly raised idle after driving, stopping, and restarting. Perhaps the TB cleaning helped the 1st problem, and I'm praying the sensor cured the second.

Oh, BTW jdm, when you unplug the coolant temp sensor, the idle drops REALLY low, but it keeps running.

I know.. it just doesn't make sense, but if it works properly.. who cares? LOL! I'm so tired worrying about it, and I appreciate all your help guys.
I hope you don't have to see any more verbiage (LMAO) from me again over this. (keep your fingers crossed!!!!!)

You guys ROCK! :smooch:
Jackie

Ya, it's one for the "be happy and don't reason why" column. I'll be bookmarking this one. When you come back in a week and say ITS FIXED I'll feel better.

We've got our fingers crossed too. To reverse the old adage, in lieu of a picture, we must lay down a thousand words. Hope that your problem is finally solved.

4Wheel......
Yes, this is a lot of verbiage (new word?)
I don’t know how new of word it is but it’s a "cool" word, and it’s usage fits very well here.


#1. I don't want another throttle body out of a junk yard. My car only has 149k and most of the cars in a junk yard are "junk" or they wouldn't be there.
There is no delaminating of any part of this throttle body. Besides, how can a brass plate delaminate? Also, I have never been able to make the TB stick intentionally... with or without the cables connected...In other words, I cannot replicate the problem.
http://i5.photobucket.com/albums/y191/AdkGal/TBafter.jpg

So in this picture of your throttle body, there is quite a bit of delamination. You are correct the throttle body is not itself delaminating.
The butterfly, (throttle plate), isn’t made of brass, it is plated steel and the plating is coming off.
You see that near were the shaft enters the throttle body and on the shaft as well!
Brass is very soft and would not work very well as a throttle plate as it would distort, bend and wear very fast. It is the same reason why I recommended the use of a "soft" brass brush, yes brass brushes come in stiff bristle form also.

The shaft is coated with a non metal coating that is also shown in this picture to have been removed by the use of strong chemical solvents.
I agree with you, if you don’t know what to look for at the wrecking yard don’t source your parts there.
Unfortunately your throttle body looks worse then most of the TB’s in the “junk yard” yours has been trashed and it is junk now. It matters not how many miles are on the car all it takes is one mistake of the use of the wrong solvents and poof history.
By the looks of it this has been going on for some time.
Hope your problem is solved, and good luck.

Look at the 'before' pics and you'll see the "delamination" was present before she cleaned it...using a toothbrush no less...so very unlikely she did it then.

The butterfly valve shaft does have a black coating, possibly a PTFE type, but where it matters is where it mates with the TB itself. If that is worn away or lost, the excessive tolerance won't allow the shaft to be positioned properly to allow the butterfly plate to rotate freely. Add in wear and aluminum galling and binding may occur.

Unless the solvents used had an acidic component, the "brass" plating would not be removed. Some engine degreasers employ organic acids (acetic or citric) as well as solvents to help loosen the caked on grime. These kinds usually have advice on the can to not spray onto intake components for good reason...it can harm the aluminum bodies as well if overused and not rinsed off thoroughly.

My only other thought is that the CC's servo motor may still have crud in it. You don't show any gap in between the CC's actuator and the black lever it presses against. Any binding in the motor could also hold the throttle open slightly. You might either try to disconnect the little shaft or loosen the adjustment so that there is a 1/4" gap (as it appears on my Cam) before it contacts the lever.

Couldn't have said it better.
The location of the delamination lends to the solvent being sprayed from the outside and traveling down the shaft to the inside of the throttle body.
This was probably done long before she tried to clean it initially.

JDM & RIP,

It's been well over a week since I replaced the coolant temperature sensor. I have driven the car in many different driving situations ie. short drives, long drives, shutting the warm car off for 15 minutes and restarting, shutting the car off 30 minutes and restarting, and I haven't had a problem in over 200+ miles.

All that crap I said about the TB and CC...forget it...its the coolant temperature sensor. Glad you found the problem, Jackie, & hats off to your mechanic for giving a correct diagnosis...sounds like he's a keeper!

Sounds like you got it. Your perseverence has paid off. Congrats! One lesson learned for everyone could be always check for codes when you have an engine related problem, light or no light.

Got a hunch you're right on the two problem deal. All your cleaning helped. The ECT was the primary problem.

Yay! I am so happy you have fixed it!
BTW, I am not a dude, LOL. Daughter of a mechanic.

The temp sensor was a great educational moment for me. :-)
I will never forget it!

:screwy: Things like that make me crazy!
Congrats :-)

Yay! I am so happy you have fixed it!
BTW, I am not a dude, LOL. Daughter of a mechanic.

The temp sensor was a great educational moment for me. :-)
I will never forget it!

:screwy: Things like that make me crazy!
Congrats :-)

Thanks Lyric Lover.....
It was driving me crazy too, but...... I really think the problem is fixed. I have driven the car over 600 miles now and it idles perfectly! Sorry if we thought you were a "dude!" Obviously, females can fix cars too, huh????

Jackie (an Adirondack gal) :iceslolan