My Cavalier Hates Me - MYSTERY PROBLEM!

Hi everybody. I'm new to posting threads here, but I've been reading through this site for quite a while -till my own problem came about. And here we go...

My 1998 Chevrolet Cavalier Z24 (2.4L 5spd.) has 136,000 miles on it. It's my daily driver.

:banghead:

Now, I've come across a problem I've had since I've owned it, where when I start the car, it starts fine, and when I pull it out of the driveway and head for the end of the street, upon trying to leave the street, it goes to immediately stall when I let go of the clutch, and I have to put it back in or the car WILL shut off in the middle of the intersection, and the only way to get it moving is to rev the motor high enough and make the clutch grab and go. Doesn't do it often enough, and I've been in my transmittion already and the clutch is good (had to replace that wonderful plastic throwout bearing).

And I only mention that problem because of this problem:

:banghead:

When I go to drive my car, if the engine is cold, it's fine. But, when the car has had time to warm up, at any time, ANY TIME, I want to accelerate at low RPM's (1000-3000), as soon as I open the throttle (more than 1/3 throttle), the car stumbles, hesitates, studders, acts like there's little fuel, etc (whatever you want to call it). Then, as soon as it's cleared the RPM range, the problem gets less frequent (or at least noticable).

This has been happening since February of this year. So, it's new. And I took it to my dealership, who have replaced the plugs three times, the boots 3 times, the coil housing twice, the coils three times, the ground once, and I have replaced the ICM (ugh). They said that they even reflashed the PCM. And surprisingly, NONE of that did ANYTHING to HELP my PROBLEM!

The dealership claims that it's not fuel related or mechanical. They stay firm with the idea that it MUST BE the secondary ignition system. I have checked for the simplest of problems, like the FPR, EVAP, PCM wires, etc. I even replaced the fuel filter. I'm running out of ideas here! I'm not mechanically declined, but this problem had me take it to the dealership, and not bang my head against the wall (cuz that really doesn't work).

:banghead: (You can literally watch me beat my head into a wall just like this when I'm away from the forum.)

You know what's even more weird? There are NO trouble codes coming off the OBD-II. The PCM thinks that everything is FINE. Fine my ASS.

Can anybody help me out with this problem? It'd put my mind at ease, and the dealership's mind as well (if they're even right).


-Ken

Mummm....after all they I would have drink a few tins and think about it !!!!!

No DTC ??? that is strange as a two headed jacko !!! Is that what the shop said or you read the Scan Tool ???

Secondary Inigition...that is the coil, plug wire and plugs. If nothing else, you think you would get a code for the O2 sensor levels.

IAC and TPS......Did the dealer check those out ???? What was the fuel pump pressure ????..one more...How about a vaccum leak ???? Read this !!

http://www.aa1car.com/library/vacleak.htm

Cheers Mate....Dont give up..just take a break, soak up some suds and hit is again.

JzJzz ...and the Man from Down Under....

It's funny you mentioned the O2 Sensor. In the midsts of this happening, the cat was replaced, and then a code for "Heated O2 sensor and invalid switching" came up, but once it was cleared, nothing has come up since. Both the dealership and I have hooked up to the OBD-II system, so I know what comes up (because I usually get a code, and with this as the problem, I'd report it to them and ask them for their opinion).

But I'm serious, no more OBD-II codes since that last one was cleared.

IAC and TPS - I am fortunate enough to have backups of these and they're new, so I replaced them already, AND cleaned out all ports to/and the throttle body itself with STP. So, I know it wasn't any of those sensors.

As for the vacuum leak, I'll check the link you gave me, but the dealership claims that it's not that. And I've been going through those lines to make sure.

And fuel pressure seems nominal still.

read on here somewhere that the 2.4 was noted for vaccumm leak around map sensor. Can`t confirm that but it was a regular poster that made the statement. Good luck.

Yeah, the MAP sensor does suck. haha I made sure to pay attention to that as I've been looking for problems. It's sealed nicely and if a vacuum leak gets out of that, I'll eat my monitor. haha. I want to work on testing the injectors today, but 100 degree weather has me thinking twice about it.

Just dont think twice about going to the cooler and getting a mug of the amber fluid.....the car can wait, till the weather cools !!!

Cheers Mate....JzJzz and Donk!!

This sounds exactly like the prob I had on my 97 z24, it was the vac line to the map was rotted out. I've heard of lots of others with similar prob, might not hurt to look again.

I've gone through the MAP sensor again, and I do have a new hose, T'd off for checking and what not, and I do not see any leaks. I even have just a plain hose and the car still does the same "studder" and "stumble when I try to open the throttle between thsoe RPM's.

Is it crazy to say that it happens more after the engine has been running a while and has had a chance to warm up a little, MORESO than when it's cold?

I was trying to take off the connectors to the injectors to try and see if one of them are bad, but my big ass hands can't fit down there. I put a screwdriver to them to hear the clicking noise and heard all relatively the same clicking speeds between the 4 of them.

I'm quickly getting more frustrated and running out of more ideas.

:banghead:

Okay, this weekend I have a small project to do, at least to see if this will help fix my car.

I'm going to carefully take off the cam covers and put in new gaskets, and if anything, it'll help stop the leaking (both intake and exhaust). And I'm going to throw new plugs in afterwards, cuz oil seems to like them better than spark.

I've also heard "timing" and seen it more than to my liking. I'm hoping it's not that, cuz I know I don't want to toy with that.

If anybody else has anything to add to my list of things this weekend, please feel free to tell me.

haha I'm going to NEED to drink after this weekend!

EGR Valve.....try clean it and the passages....the ETC, it tells the computer the engine is cold or hot ..... check these out ....can't hurt !!!!

If all else fails.....by all means....have slab of the cold tinny !!

Cheer Mate.......JzJzz ....time to visit my favorite pub !!

Okay, so I spent last weekend doing some work....

And I opted out of doing the camshaft gaskets.

Alldata calls for roughly 9 hrs labor and I'm not a master mechanic. I'm an ADHD mechanic... so... that calculates into 10 days. haha

SO, I did to the plugs, and I looked a the old ones (which are only a month old) and they seemed okay, not fouled with oil, tho smelled like it of course. They were a little ashy and white (maybe running rich, incorrect gap, or heat range, idk).

But, I put in the new plugs and have been driving her since, and she hasn't been causing her usual studder and hesitation (knock on wood). As far as the cam covers go... that's why God made JB-Weld. I'm going to brakecleen both covers and have my way with JB in the next weekend. I just don't feel like I can do the job and if All-Data is calling for that kinda labor and considering that GM needs to do it in less or under warranty to make money, I can't afford that kinda bill for 4 gaskets.

3.5 hrs for a waterpump.. but 9 hrs for gaskets... wtf?!

I'll still keep you guys posted as to this problem. Let's hope it stays away now.

From your first post.
This has been happening since February of this year. So, it's new. And I took it to my dealership, who have replaced the plugs three times, the boots 3 times, the coil housing twice, the coils three times, the ground once, and I have replaced the ICM (ugh). They said that they even reflashed the PCM. And surprisingly, NONE of that did ANYTHING to HELP my PROBLEM!


I am a little lost..but for me that is normal ???? All the previous work, plugs, wires, etc....did nothing!!! Why now ?? when you changed the plugs again, everything is fine ????

Did you use difference plug, gap or heat range ??? or are the "Wrench Gods" feeling sorry for you ??

Cheers Mate, JzJzz ....

You know, I think it's the "Wrench Gods".

The old plugs, before the start of problems, were Platinum 4's. Once they went bad, they kept replacing them with AC's. I figured it could have been "off-gapped" or they put in the wrong heat range.

If you play with that theory, then it'd take me back to after the first incident, when they found that the ground insulator strap was missing and replaced it. From then on, it could have been the plugs all along, but they kept replacing them with the same plug.

I do think that the leaky camshaft covers are contributing to the plugs fouling, but idk.

All I know now is that it's been working good since I put new Platinum 4's in.

But I'm not done with anything yet. I am going to seal those covers. It's got 136K on it, and I love and hate my cavi too much to get rid of it now.

That is the right response....Now you are thinking !!!! :) Good Job Mate !!!
I might even hire you in my shop !!!! but all I do is bikes...some cars, but only for the poor, old, lonely and women that bring beer !!!

Cheers Mate, have a Foster's day !!! JzJzz .....

PS ...Dont get rid of the Cav....unless you get a Chopper...the " Wrench Gods" may get pissed !!!

If I was like other people out there, I'd have gotten rid of my cavi as soon as the payments were done.

Instead, I spent part of today prepping the interior part of the door for it's paint.

This car and I have been through it all. It's treated me better than any girl I've ever been with. She likes to get dirty and never minds when I get a little rough with it. hahahaha

Okay... back to reality... nope, still here.. haha I'm just waiting for the rain to end, so I can work on the Cams. Until then, it's a beer here, and a beer there, and I'm prepping myself for "fun".

maybe your catalytic converter melted, would explain the o2 sensor malfunction

Nah, the cat is brand new. (You should have seen the old one! haha)

Since I JB-Cold Welded the upper camshaft oil guides, I haven't *knock on wood* noticed anything wrong. I think that the mix between the plugs and the guides were causing this shitload of problems.

Now I can feel the hp I've put into the car.

So I decided that while I've been in the midsts of that that I'd continue working on the interior of the car and I've gotta say it looks good. I'd put up some pics if I knew how to feed them onto these threads.

Idk guys, but I take pride in my Chevy and people keep telling me to get rid of it but like I said, I love and hate my Cavi and we've been through it all.

I really hope someone who has my problem finds relief... this was taking way too long, and nobody else could come up with this problem.

You know I'm too afraid to look under my own hood to see how the leaking is... hahahhaha :lol2: