check fuel pressure.... moisture in distributor cap

i can't tell what kind of Jeep it is 300 miles away

 

its an I6.

 

Also a classic sign of a weak battery. The battery can be just strong enough to crank the engine, but the voltage dips below 10.2V and the pcm freaks out. Check the terminals and clean as necessary. Load test the battery as well.

 

Agreed that could be an issue also.

 

anyone know how much for a new IAC

 

$42 from Autozone. (Based on my 5.2L V8)

 

Hey i had the same prob... I load tested my batt and it was bad so i bought a new one and i cleaned my TB and my mass air sensore and it runs like a raped ape ha hahaaa

 

the IAC might just need to be cleaned. they get a large amount of carbon build up on it. i would try just taking it out and wiping down the IAC and the bracket it slides into first. could save you 40 bucks

 

what do you guys think is better for cleaning the IAC with out taking it out. TB cleaner or MCCC?

 

i think TB cleaner would be fine for it.... but i would really recommend just taking it out and cleaning it.... its just a matter of unplugging it and 2 t20 torx bolts. it took me about 10 minutes to take it off, clean it, and put it back on.

 

yeah I know but its for someone who is not going to do that haha. I am trying to keep it very simple.

 

look about 1/2 way down the page at a post from woody for cleaning the IAC......hopefully this helps your friend with some pics.

http://www.jeepforum.com/forum/showthread.php?p=2215668

 

You are telling me about the FAQ lol are you serious!

Just Kidding

:teehee:

Thank you for actuly reading the FAQ and knowing whats in it.

See Nash they learn.:shhh:

 

It would appear that the IAC valve is stuck in the closed position. If so, then there is absolutely no way to get air into the throttle body since the throttle plate is always closed during start-up and idle.

 

Three things that I can dream up that can cause this:
1- the actuator died in the closed position.
2- the electrical harness has a bad connection.
3- the TPS is bad and sending a high voltage when the throttle plate is closed, which would tell the IAC to close

 

that was what I was wondering about the TPS, what also indicates a bad TPS? I think it does accuate a little bit cause it will somtimes start with out the foot on the gas. I am just trying to limit the options on what is wrong with it.

 

yea well not gonna lie.... the FAQ has been able to answer alot of my questions :2thumbsup:

helps keep down on these duplicate posts all the time :teehee:

:thumbsup:

 

Mine died on me on a road trip one day, had to feather the throttle to keep it running. Noticed as soon as I let it drop below 1000 rpm or so the volt gauge would take a severe dive and it would stall. Limped it to a parts store, bought an alternator and swapped it out and it has been good ever since.

 

Well you can only access the mass air sensor if you take it out it is covered and like KMD said its real easy took me like 30 seconds but i took my whole tb off and cleaned it its a whole lot easier and i used tb cleaner on the tb and mass air cleaner on the mass air. And after i did all that is has not died at all and runs smoother and idles nice.

 

I dont think there is a mass air flow on the older TB's. I was just trying to narrow it down, i wanted to make sure it was not something else like the TPS or CPS. That would cause the jeep only to run with ones foot down on the gas.

 

I would think if the TPS was bad the check engine light would be on. At least that's how it was for me.

IAC - $37 from PepBoys

 

Jeep not starting

About a year ago, we had a mobile mechanic come and take a look at the 1997 Jeep Grand Cherokee Laredo V8 5.2. He found one issue. We recently had a similar issue but without the overall problem. If your in a hurry jump to the conclusion.

Last year:
We were having the same problems as you guys. One random day the Jeep stalled out in a busy intersection while my wife was driving. She had to push it on her own (no good Samaritans) to the corner gas station. The thing would not start and we had to have it towed home. We had the mobile mechanic come out and he came up with short in the PCM that was causing the Jeep to lose power and stall. It was also having transmission issues. The '97 Grand Cherokee would not shift out of first into second. I can't remember all of the issues, but we went to the junkyard and found a nice match for the PCM and did the swap.

Recent:
This last Memorial Weekend, my wife and I went camping in her Grand Cherokee. We got to the location, went out for drives and had no issues. We packed up and began our decent back to civilization, the Jeep wouldn't start. There was a rapid clicking in the passenger side dash. There was no power. Went and grabbed the jumpstarter, hooked it up and started right up. Immediately, the Grand Cherokee stalled out. We tried this several times and got to the last crank on the jumstarter. Then decided to keep a foot on the gas and hit it!!! We made it all the way home (100 miles or so). Praise Jesus, we had mostly green lights and a clever "Neutral" "REV" California stop! We pulled in the driveway, turned to back in and BAM!!, DEAD!! would not start. I charged the jumpstarter and check out some forums on the issue. One said to check for a corroded positive cable that is causing the clicking due to low voltage. I bought a positive cable because I did see the lights brighten a bit when I was moving the cables around. I went out and gerry rigged the new cable on to the system (with the old cable removed) and proceeded to fail to start. I regrouped and googled "jeep grand cherokee won't stay running" and found this post that said to change the IAC (Idle Air Control). I disconected the IAC, didn't start. Took the IAC off and cleaned it with brake cleaner, Jeep started, but wouldn't stay on. When I held the gas and let it out gradually, I was able to get it to idle. On a whim, I took the IAC out and started the Jeep without it. The jeep started right up and didn't stall. It had great suction where the IAC should be. I placed the IAC back into its slot while the Jeep was running and it expectedly stalled within seconds. Went to the local auto store, replaced the IAC and runs beautifully. I don't know how the whole system lost power and wouldn't start, but as for now it is starting and running. I will hold on to the positive cable, just in case.

Conclusion: Thanks Guys
Transmission shifting problems = PCM shorting (replace)
Not starting, stalling out = IAC (Idle Air Control) replace

 

Hello all,

PLEASE read my following post. I am back from college for Xmas break and need to figure out the problem that I've been stumped on for months now. I just do not know whether it's a carburetor problem (600 CFM too big), just timing problem, or something else. Any bit of help is greatly appreciated!

http://www.jeepforum.com/forum/f8/c.../cj5-starts-while-pumping-pedal-runs-3-6-seconds-then-slowly-dies-down-2635898/

 

I'm really not sure what you think you're gonna get out of this.

You're posting in a dead thread about a vehicle you don't have. With an engine you don't have. A fuel system you don't have. You started a thread in the right place to get help with your problem. Why did you feel the need to post it here?

 

Wow, ancient thread. But for those of you who land here looking for answers to the OP's problem...

I also had this issue as described. Thought it was sticky throttle plate or IAC. Cleaned them. Not fixed.

It turned out to be a poor/loose connection from Battery Neg terminal to the Body Ground. The cable was not crimped tightly enough in the battery clamp. There was enough contact to start when motionless. It looked ok visually. but as soon as you moved and turned on other devices, the vibration or current draw was enough to break the connection, or make it intermittent enough that the PCM got confused.

New clamp and cables fixed it. While doing the work, I also cleaned up the Engine-to-body Ground strap connections.

 

"I'm really not sure what you think you're gonna get out of this.
You're posting in a dead thread about a vehicle you don't have. With an engine you don't have. A fuel system you don't have. You started a thread in the right place to get help with your problem. Why did you feel the need to post it here?"

Who are you directing this towards?

 

DrtyJrz609:

I believe that kg6mov was directing the comment toward you.

You have cross-posted your issue about your CJ5 4.2L engine w/carborator, into a sub forum that is dedicated to the "ZJ Grand Cherokee", a trim line which only used 4L i6, 5.2L V8 and 5.9L V8 engines, and Fuel Injection.

Our experiences may or may not help you.