93GC cranks but no start, check engine light!!

hi, I'm having trouble with my jeep laredo
It cranks but doens't start
It takes like 4 times to start but today it took like 10 times in the cold.

I noticed that it doesn't start unless the check engine is on. all the other lights come on exept the check engine light. It takes a few times to appear.

I don't think it's the fuel pump cuz i hear it clicking immedtly after turning it on. I also don't have any problems with acceleration or idling.

I'm going to change either the crankshaft postion sensor or camshaft....
but I don't know which .

I recently did a tune up and I have spark.


need help asap

thanx

hi, I'm having trouble with my jeep laredo
It cranks but doens't start
It takes like 4 times to start but today it took like 10 times in the cold.

I noticed that it doesn't start unless the check engine is on. all the other lights come on exept the check engine light. It takes a few times to appear.

I don't think it's the fuel pump cuz i hear it clicking immedtly after turning it on. I also don't have any problems with acceleration or idling.

I'm going to change either the crankshaft postion sensor or camshaft....
but I don't know which .

I recently did a tune up and I have spark.


need help asap

thanx

I just let some mechanic take a lokk at it . He said he needs to dianose it for 75 lol.
I checked the codes and got code number 13. does this have anything to do with my problem. I also told him that it might be from the CPS but he doubted it saying that it has nothing to do with the check engine light. and that it would never start up.

He said it might be the computerbut i don't trust him lol.

as i said my car doesn't start until it sees the check engine light and the mechanic says it always has to be on and that the CPS doens't effect the check engine light.

thanx

From what I could find a 13 check engine code is - No difference recognized between the engine MAP reading and the barometric (atmosphere) pressure reading from start-up. So you may want to have the MAP sensor checked out.
ByronP

I just let some mechanic take a lokk at it . He said he needs to dianose it for 75 lol.
I checked the codes and got code number 13. does this have anything to do with my problem. I also told him that it might be from the CPS but he doubted it saying that it has nothing to do with the check engine light. and that it would never start up.

He said it might be the computerbut i don't trust him lol.

as i said my car doesn't start until it sees the check engine light and the mechanic says it always has to be on and that the CPS doens't effect the check engine light.

thanx

how much would it cost thanx

I think a new ECU is around $300 and NAPA shows a new MAP is $40 for the I6 and $80 for the V8. Not sure what it would cost to get it checked. You may be able to test it with a decent multimeter but I can't say for sure as I've never had to diagnose one.
ByronP

If it has Spark and Injector pulse then you don't need a Crank sensor! Just because you hear the fuel pump doesn't mean you have adequate fuel pressure. You NEED to check your fuel pressure!
It should be 31 PSI at idle, 39 PSI with the vacuum hose off of the fuel pressure regulator.

it sounds like you need a pcm.thats what turns the check engine light on and if it doesnt come on when you first turn the key on it wont start.you can try turnung the key on and wiggle the connector at the pcm and see if it gets the light to come on.I have seen this problem several times.You might want to check with a dealer on a mopar reman pcm.They had some but off the top of my head i dont know if they have one for yours.

it sounds like you need a pcm.thats what turns the check engine light on and if it doesnt come on when you first turn the key on it wont start.you can try turnung the key on and wiggle the connector at the pcm and see if it gets the light to come on.I have seen this problem several times.You might want to check with a dealer on a mopar reman pcm.They had some but off the top of my head i dont know if they have one for yours.


bump

If it has Spark and Injector pulse then you don't need a Crank sensor! Just because you hear the fuel pump doesn't mean you have adequate fuel pressure. You NEED to check your fuel pressure!
It should be 31 PSI at idle, 39 PSI with the vacuum hose off of the fuel pressure regulator.


i did a complete test.
computser scanner shows nothing. i get spark. fuel pressure is good.

fuel pump/relays are good.
could it be from the battery? when i put the key to the on position, i only get like 9 or 10 volts and then after firing it up it goes to 14 . is this normal.

my dealer says that it could be the igntion switch.

he says there is something preventing the fuel pump to kick on (because check engine light takes time to come on)
he' s gone crazy and so have i


i need some help plz

hi, I'm having trouble with my jeep laredo
It cranks but doens't start
It takes like 4 times to start but today it took like 10 times in the cold.

I noticed that it doesn't start unless the check engine is on. all the other lights come on exept the check engine light. It takes a few times to appear.

I don't think it's the fuel pump cuz i hear it clicking immedtly after turning it on. I also don't have any problems with acceleration or idling.

I'm going to change either the crankshaft postion sensor or camshaft....
but I don't know which .

I recently did a tune up and I have spark.


need help asap

thanx


Code 13- Idicates a problem with the Manifold Absolute Pressure Sensor vacuum source.

your problem is not the Camshaft Position sensor, if it was the camshaft Position Sensor, it wouldn't crank at all. but it could be the Crankshaft Position Sensor. but I would have the MAP sensor check out and replaced. b4 you do anything, I am willing to bet that is the problem.

Sry, for my last answer I kinda jumped the gun and didn't read all replys.
well since u have spark, I doubt it is the Crank sensor. but I would go ahead and have the MAP Sensor checkd out, doubt if that has anything to do with the Check Engine light not coming on at start-up.

have u ever sprayed any water in ur engine compartment. u might have to disconnect the wires from the PCM, maybe u have condensation in the connectors, and it is preventing it from starting, someone else had that problem with their jeep not starting and thats what the whole problem was. try to d/c it and let it air dry for a couple hours, that might help.

yes. the place i bought it from cleaned the whole engine compartment with a high pressure hose or whatever.

now , where's the pcs connectors located?
im gonna try this one
thanx alot bro

i really appreicaite it

the PCM connector is loacted on the PCM, it is on the passenger side firewall in the engine compartment, should be behind the Colant Reserve Tank. there is one big connector, about 5" long and 2" wide, and there is a bolt right in the center, just loosen it all the way and pull it out.

the PCM connector is loacted on the PCM, it is on the passenger side firewall in the engine compartment, should be behind the Colant Reserve Tank. there is one big connector, about 5" long and 2" wide, and there is a bolt right in the center, just loosen it all the way and pull it out.


could it be the battery?
cuz i only get 9-10 volts when the key is turned onto the on position. but after starting the car up. it goes to 13-14

is this normal or shoud i just buy a new battery. thaxn

I doubt it being the battery I thought the same thing with mine but it seems to be normal. I have tested the battery, b4 trying to start it in the morning with a MULTIMETER and it tested out good, should be between 11.8 volts and 12.6 volts when not running.
I suppose it could be the Ingition Switch. just check, when it won't start just turn the key to the ON position and then open the gas cap and listen for the fuel pump, on alot of cars u can hear it turning on while sitting in the drivers seat, but I even found it hard to hear while listen down by the gas tank. so I opened the gas cap and listened.

my mechanic is now telling me it sometimes gets no spark and it could be the crank shaft position sensor.

but does that have anything to do with the chech engine light not coming on

thanx

The place you bought it from probably took the bulb out of the dash. I see that happen all of the time with used car lots.

You need to go back to the basics and stop jumping all over the place.

A)Spark @ the plugs?
B)Injector Pulse @ the injectors?
C)Fuel Pressure
D)Compression
E)Timing

Let us know the results.

if you have factory security system, I have a ecm you can have for $100. I'll pay shipping. I was trying to solve alarm issue and turned out to be a sensor(doesn't it always?)

Tom Denkler

email: tdenkler3853@earthlink.net

The place you bought it from probably took the bulb out of the dash. I see that happen all of the time with used car lots.

You need to go back to the basics and stop jumping all over the place.

A)Spark @ the plugs?
B)Injector Pulse @ the injectors?
C)Fuel Pressure
D)Compression
E)Timing

Let us know the results.



what bulb are you talking about

and i do have all those u listed

thanx

I thought you had said your check engine light was not coming on. The bulb in the dash is what I was talking about.

So you have spark available at the plugs, you have adequate fuel pressure, you have injector pulse, you have good compression, and correct timing. Then let's look at it like this, what else could cause the engine not to start? Either the spark plugs are fouled possibly due to over fueling or being soaked in coolant. What could cause too much fuel? A faulty MAP reading or engine coolant temp would be the most likely cause of it actually not even starting. If your TPS was faulty it would set clear flood mode if it was reading over 4.3V at idle but you would have no injector pulse which you said you had. Here is what I would suggest. Pull all of the spark plugs and check them. If they are wet with fuel you have an overly rich condition. Check the MAP and engine Coolant temp sensors. Replace the spark plugs and make sure you have no obstructions in the induction system, like a mouse nest in the air cleaner. Good luck.

the CHECK ENGINE light is effected by the Crankshaft Position Sensor. whe the CHECK ENGINE light comes on, during ignitial start up or when key put in the ON posistion the light comes on (this tells u that the engine has ran the innitial diagnosis and everything checks out) most common reason for it not to come on is b/c of the Crankshaft Posistion Sensor, the computer is not getting a proper read or it is just not responding theref or the computer won't allow any othe operation to perform( Fuel pump, Injectors, Ignition Coil).
take the gas cap off of the Fuel Tank, and have someone turn the key to the ON posistion if u here a whirring sound then the Fuel Pump is working correctly. if not then it is most likely the CPS. the fuel pump could still operate and have u may still have a bad CPS. I dunno, bottum line I would start at the CPS. change it and c what happens

hi everyone.

I just go my car back from some mechanic and he said that there's no fuel, pressure. spark.igntion pulse . etc...

he said it could be the wires that go to the computer or the computer itself could be bad.
he said that there's like 30 wires to check and that would cost 125 .damn it

I just took a look at the wires and saw one pink wire which was bare for like an inch but wasnt really touching anything.

could that be my problem . lol i hope so

well if it's not touching any metal, then I would say no, but put some electrical tape around it just incase.

but what u have described sounds like the Crankshaft Posistion Sensor is bad. I would check that out 1st.

read what I wrote above.

this mechanic said that the crankshaft position sensor was good.
he said it wasn't getting any ground or whatever to it. neither do all the fuses and relays etc...

how much would it cost for a cps? with labor and everything.

i kept telling this guy it may be the cps but he argued heavly that its the computer

depending on which engine u have. 5.2L is 41.99 . and 4.0 there is a couple brands ranging from 42.99 to 65.99. check autozone.

I was speaking with anopther guy who is changing his, and he was gonna have the dealer do it, but it would cost $400. and believe me it is not worth $400 it will take like an hour-2hours tops if u do it urself. if u need directions email me Joe, dksob81@hotmail.com

I meant instructions.....lol email me dksob81@hotmail.com

ok so my mechanic changed the crank sensor but the car started running like crap. rpm's were jumping and the car was like farting lol.

so he put the old crank sensor back in .the car runs fine now but it still has the major problem.
maybe he put in a wrong or faulty sensor.
he's ordering a new one by saturday.

there is something preventing the damn fuel pump, ignition , spark plugs etc.. to work.

i"m thinking that it could be the factory alarm .
how can i permantly disbale it.???

also, i have a question. when u put ur key in and on to the on position and wait a few seconds .
Does the security light come on on the dash?

thanxxxxxxxx

plus when my mechanic hooks up his computer to the truck. it says no data.

I woul dhave to say that the new CPS (Crank position Sensor) was faulty. and no the Security light doesn't come on in my jeep (1994 Jeep grand Cherokee Limited 5.2L) when I turn the key to the ON position. I will check again in the morning just to make sure.

the security light comes on after leaving the key in for like 40 seconds
can u plz check urs

sorry I forgot to check this morning, I will check as soon as I get home.

Dude! Any developments on your starting problem? I was poring over the forums (fori?) and your case is EXACTLY like mine - ie: no check-engine light = no start. If/when it flashes on, I know it will start.
Mine's been in the shop for weeks, trying all sorts of stuff (crank sensor etc.) but no dice.

Just curious if / how yours was solved.

Thanks

Dude! Any developments on your starting problem? I was poring over the forums (fori?) and your case is EXACTLY like mine - ie: no check-engine light = no start. If/when it flashes on, I know it will start.
Mine's been in the shop for weeks, trying all sorts of stuff (crank sensor etc.) but no dice.

Just curious if / how yours was solved.

Thanks
HI, HAVE YOU CHANGED THE CRANKSHAFT SENSOR. DO YOU HAVE SPARK AT THE COIL WIRE. YEAR, MAKE, MODEL AND ENGINE , AND ANY OTHER INFO YOU HAVE ON PROBLEM DALE jeepman600@aol.com :2cents:

Aha! The famous jeepman! I almost emailed you before posting.
Crankshaft sensor replaced - no dice. It is a 93 Grand Cherokee limited with the inline six cylinder engine and selectrac 4x4.
I'm starting to suspect the ECM module or connections to it, maybe the relay (thus the no check-engine light when it won't fire).
Thanks

Aha! The famous jeepman! I almost emailed you before posting.
Crankshaft sensor replaced - no dice. It is a 93 Grand Cherokee limited with the inline six cylinder engine and selectrac 4x4.
I'm starting to suspect the ECM module or connections to it, maybe the relay (thus the no check-engine light when it won't fire).
Thanks


Does the gauges on dash work when you turn key on dale
can you hear the fuel pump relay click when you turn key on

The gauges work; nope, can't hear the pump.
Also, this started (could be a coincidence) when the weather turned colder. Just when we need a Jeep most.
However, when the Check-engine light DOES light up, then it DOES start, and I can hear the pump, and a major click/buzz from pax-side firewall (near the ECM?)

The gauges work; nope, can't hear the pump.
Also, this started (could be a coincidence) when the weather turned colder. Just when we need a Jeep most.
However, when the Check-engine light DOES light up, then it DOES start, and I can hear the pump, and a major click/buzz from pax-side firewall (near the ECM?)
if yours has a power distribution box remove lid look and see what relay is for ASD change the ASD relay with one of the other relays, they are all the same. email me i can get back faster jeepman600@aol.com

DARKO, was the brand of CPS you used Borge Warner or something like that, if so replace it with a different brand EICHLIN is a good one.

DARKO, was the brand of CPS you used Borge Warner or something like that, if so replace it with a different brand EICHLIN is a good one.



dude. u need to replace the computer. just stop poring money into the jeep and get a new computer.
all my problems have been gone ever since.

Thanks for the info! I was hoping to hear from you as the symptoms are bang-on same as yours. Now the hunt begins. Car-part.com lists them but I've never seen so many options to choose from. Have to check my data.
Thanks

And...voila! Same thing. Replaced the computer and that did it. Still waiting for the mech's bill for all the dorking he did before this...

Detail shop i took my GC to a while back would not touch engine compartment due to the sensors being to fragile.
Check the connector at the MAP sensor for corrosion
go to radio shack and pick up a can of contact cleaner and try cleaning the connector to MAP before you replace it.

Dude! Any developments on your starting problem? I was poring over the forums (fori?) and your case is EXACTLY like mine - ie: no check-engine light = no start. If/when it flashes on, I know it will start.
Mine's been in the shop for weeks, trying all sorts of stuff (crank sensor etc.) but no dice.

Just curious if / how yours was solved.

Thanks

Darko, so the replaced computer fixed all your problems? I have the EXACT problem - plus - my alarm has been going off at strange hours of the night. In your experience, do you think that the starting issues and the alarm are connected in some way?
Glad to hear the jeep is all better now.
thanks

So far so good; the problem hasn't come back, although one morning I had a scare. But yes - the computer did it. I got a reman online; 275 plus core deposit 100 which you get back. Seems cheaper in the long run, and saves a lot of heartache each time a new fix doesn't do it.
Not sure about the alarm affecting the computer; mine wasn't bleating, except after looooong cranking it would beep a couple of times.

Nart86,
I would like to know if replacing the PCM was something that a guy could do on his own? I had the very same problem that you have, but it mysteriously went away. Now, it is back. You had mentioned that you got the computer replaced (computer=PCM?) and that this solved your starting/check engine light problem. Is it simple to replace?
Cheers,
PrestonP

I would also like to ask some of the famous forum experts (like Dale and dksob81) about their opinions on this problem and the proposed solution. Why do you think that the check engine light refuses to come on? Thanks, you guys are brilliant!

Nart86,
I would like to know if replacing the PCM was something that a guy could do on his own? I had the very same problem that you have, but it mysteriously went away. Now, it is back. You had mentioned that you got the computer replaced (computer=PCM?) and that this solved your starting/check engine light problem. Is it simple to replace?
Cheers,
PrestonP

I would also like to ask some of the famous forum experts (like Dale and dksob81) about their opinions on this problem and the proposed solution. Why do you think that the check engine light refuses to come on? Thanks, you guys are brilliant!


HI, THANKS FOR THE HYPE. WHAT EXACTLY IS YOUR PROBLEM ALOT OF TIMES THERE IS JUST SOMETHING A LITTLE DIFFERENT ON EACH VEHICLE. THE COMPUTER IS BASICALLY A PLUG IN DEAL. SOMETIMES, IF YOU CHANGE IT CHECK AND CLEAN THE PLUG CONNECTIONS, LOOK TO SEE IF ALL THE WIRES ARE A GOOD CONNECTION. IF YOU CHANGE IT JUST BE SURE TO DISCONNECT THE BATTERY BEFORE DOING HOPE THIS HELPS DALE

Dale, thanks for your help. I've just been under the hood and I unplugged the main connection into the PCM and wiped away dust, and other bits that may interfere with the connection. tried to start it again, but nothing. I have a 94 Jeep grand cherokee that will only start once the "check ongine" light clicks on. I put in the key, turn to the on position, and if there is no light, it will turn try to start (starter is working well) but I can guarantee that it will not start up. However, once the "check engine" shows up, it starts and drives nicely. Usually it takes a minute or two of trying before it starts, today - nothing. No matter what I try, the light doesn't show up, and the Jeep doesn't start. I will be very close to my computer today, thanks for your help - I'm going back out to tinker some more...
PrestonP

Well, I finally got it started. I prayed, that may have helped.
Actually, besides divine intervention, I really don't know what finally got it running. Like I predicted, the "check engine" light came on and with one turn of the key - vrooom. When I turned it off and tried again, it worked. But when I left if for 20 minutes and came back to it - it took several good tries and another prayer before the "check engine" light came on - then she started nicely. Dale, I sure thank you for your help and I hope I can do you proud by getting her to start on time, everytime.
Cheers,
PrestonP

Well, I finally got it started. I prayed, that may have helped.
Actually, besides divine intervention, I really don't know what finally got it running. Like I predicted, the "check engine" light came on and with one turn of the key - vrooom. When I turned it off and tried again, it worked. But when I left if for 20 minutes and came back to it - it took several good tries and another prayer before the "check engine" light came on - then she started nicely. Dale, I sure thank you for your help and I hope I can do you proud by getting her to start on time, everytime.
Cheers,
PrestonP


USUALLY WE'VE RUN INTO FRAYED WIRES AND BURNT WIRES GOING TO CRANKSHAFT SENSOR. THE CONNECTORS ON THE CRANKSHAFT AND CAMSHAFT SENSOR CAUSE A LOT OF HEADACHES. LOT OF TIMES WIGGLING THE CONNECTORS WILL LEAD TO THE NO START PROBLEMS.
THE 93-96 GC'S SEEMED TO HAVE A LOT OF WITH COMPUTERS AND BAD CONNECTORS ON THEM DALE :smokin: :grinyes:

Dale,
What is the easiest way to access the Crankshaft sensor? My manual says it is on top of the transmission housing- is that true? What would you suggest?
Preston

Dale,
What is the easiest way to access the Crankshaft sensor? My manual says it is on top of the transmission housing- is that true? What would you suggest?
Preston

Give me a holler at jeepman600@sbcglobal.net I :naughty: 'll send picture and instructions Dale

your chances that your computer is going bad are 98% and you can ask me for information about where to get a cheap PCM/ECM computer not from the foolish dealership, i made the same on my jeep and my problem is solved, i could tell you my PCM cost 240 dollars and i could install it by myself

sounds great, let me know the details...Where can I get a new PCM? I live in Canada...so I would have to find a source up here...
Thanks so much,
Preston

Preston
send me an email to my account, and i will let you know, because i don't think they don't allow to post websites here, thank you!

the problem on the jeeps are the computers, the stock ones are of bad quality because they want to save money and compromise quality, that's why all of us have problems with our cars due to a bad computer, i could predict the lifespan of a computer: 10-12 years and that's all

I am ordering one (computer) today from Schucks for my 93 Wrangler (4.0 l6) because of the same problem. There are several part numbers. You need to match #'s with what you have. My reman. comp. is $131 plus $70 core.

That seems like a great price. I called the dealer and they want $800 for one! Great find! Are the reman comps. worth it? Let me know how it works out for you
Cheers
PrestonP

Hay the map code is most likely because the engine hasn't crank after so many starts. It is the running problem that has cause the code. Just because you get a code doesn't mean it is bad. It just said it didn't see the change but why not? Because it did not crank is why. And also I have never had a map sensor to stop one from starting. When it is bad most of time it will run very rich.

That seems like a great price. I called the dealer and they want $800 for one! Great find! Are the reman comps. worth it? Let me know how it works out for you


They had to special order and it is supposed to ship on the 18th. Everywhere I looked it had to be special ordered though so no big deal. There were two different part numbers and one was $170 and the other was $130. I was lucky I guess that I needed the cheaper one.

I am crossing my fingers that this will fix the problem.

I WILL post a response so others (the many) with this same problem can benefit.:)