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tseliosbrad · 07-06-2010, 10:41 AM

I am new to this forum and needed some help... I'm having a 1994 laredo 5.2l automatic with 220k

In the morning when I try and start it it doesn't turn on unless I get the check engine light to turn on before I crank it, then the light turns off and for about 10 minutes she wants to stall if I let the R's down too much.

Before I bought the jeep the other day the lady said she had taken it in to get it fixed and they replaced the fuel pump and the car still did it. Then she took it to Autozone and had it scanned and she claims its the ECM. I guess when the Jeep starts acting up its not getting and power to the fuel pump she said.

Could this be the cause of the relay or the ECM? Is this a common problem with jeeps?

And also this jeep and my dodge shadow has a problem with the cruise control. Works sometimes (only works if I tap the brake and get it to upshift)
Is this another common problem too?

sadass · 07-06-2010, 04:43 PM

My first suggestion will be to Disconnect Battery. I would disconnect the big connectors going to the PCM. (ECM). re seat the connectors and try it again.

The PCM is found Under the hood on the fire wall Passenger side behind the Engine coolant reservoir.
Also, check for Fault codes. This is a 94 so you can use the key cycle method to retrieve stored codes.
These PCM's have had issues with 3 of the capacitors on the board leaking.
as well as many have had issues with the connector's and there contact's

Check out Rusty's95zj post #9 on this link as well.
http://www.cherokeetalk.com/forum/f39/93-grand-cherokee-fuel-problems-9485/

In closing, It does not sound like you factory alarm or (Auto Shut Down) circuit (ASD Relay), because you say it runs if you hold the gas. I am Leaning toward one of the two PCM problems . each can be fixed with out purchasing a new PCM> IF you need the Leaky capacitor repair link , Let me know but start with messing with the connector first.

Good luck and report back!

tseliosbrad · 07-06-2010, 05:38 PM

Great answer!!! It's so hard to find people to answer questions with great answers

I will reply back asap (in a day or 2)

I thought that might be a problem

tseliosbrad · 07-07-2010, 09:15 PM

Nope... didn't work

I cleaned the plug really really good, took the cover off the PCM and looked at the capacitors and they looked fine, made sure that the plug was in all the way, still the same problem, went to the junk yard and found out why they call them junk yards because 3 out of 4 of the PCM's where junk.
bought the good PCM for $75 and when I got home it still was wanting to stall a few times so now I have 2 good PCM's now (I'll just sell the other one on Craigslist or something)

So I was dicking around with it for an hour or so when it was wanting to stall and I tested it for Vac leaks looked for anything out of the ordinary and was listening to the brand new fuel pump and relay kicking on and off because thats what it sounds like when its acting up.

It's like it isn't holding the fuel in the rail or its like when you let off the gas the R's don't stop at where they're sopposed to and they drop too low and either want to stall or fight to stay alive.

I also noticed that it has a Holley throttle body on it... is that stock? and could it be the MAP sensor and if so how do I test it? Or could it be something else?

O and I just found a link online... take a look at this guys problem and the other guys answer too

http://www.fixya.com/cars/t5192245-94_jeep_grand_cherokee_stalls_after