Jeep Engine Stalls Just After Startup

Bill, thanks for the tip, and I will try that if it happens again. But, what is the ultimate cure -- a more permanent solution ??

I guess if it only happened once a month or so, then I could just use your method and all would be ok..............

I will see how it goes. I will enjoy any other postings on this, as my wife is now hesitant to drive it for the next week or so until we know what it is going to do.

--James--

James Nipper did pass the time by typing:

Any number of things could be doing this. From a simple bad battery ground to sensor failures.

Pull the engine codes and let us know, ok.

By the way, pumping the gas or "goosing it" only works for carbureted vehicles, doesn't do squat for fuel injected ones.

Sounds like your not getting fuel. The ecm primes the fuel system when you first turn the key on (runs the pump for 2 sec) then shuts off. once the engine starts and is running it turns the pump on continously once it "sees" oil pressure, and various other signal from other sensors. the engine can run for a few seconds on this initial "prime", then shut off. one problem i have come across on the same vehicle as yours was a faulty ignition switch not supplying power to the main relay causing the vehicle to stall after start-up. are all of the guages/lights on the dash functioning when it stalls? as suggested , check ecm codes. what you might try is to get somone else to try starting it while listening for the fuel pump. you can do this by putting your ear near the fuel tank and listening for a hissing/humming sound or by removing the fuel filler cap and listening there. see what happens first, either the engine stalls and the pump runs for a second after or the pump stops and the engine stalls.

Shawn

My 18 year old son did that trick about ignition on / ignition off 3 times to get the error code. It came up with P1685. We looked this up, and the culprit is

The engine controller has received an invalid key from the SKIM.

SKIM is the Sentry Key Immobilizer Module. As I had commented in my post, it was acting just like it did one time right after I bought the car 4 years ago, when I had a regular key (no chip) made and tried to start the car.

For now, I am hoping that it was just a minor glitch, and will not happen again.

I do thank everyone, including Bill, Doug, and Shawn for their helpful info !! Getting the code was a good tool.

--James--

This just happened to my wife's 99 Limited (73K mi) on Friday. I would believe the fuel pressure thoughts, the CPS was just replaced.

I got some electrical contact spray and did this today. So far it starts consistently and idles at about 500, but the idle is kinda choppy. It fluctuates +/- 100 RPM or so. It doesn't sputter per se, it just kinda sweeps up & down on the tach.

I also got some throttle body cleaner and a toothbrush and cleaned the Idle Air Pasage and both sides of the butterfly and the inside of the throttle body cylinder.

While it didn't enjoy starting immediately after spraying the cleaner inside the throttle body, I wiped it out with a clean rag and after one start things were ok.

What I'm wondering is what the specs say the idle should be. If you're just joining us, it's a 2000 Cherokee Freedom 6 cyl 4.0.

Thanks!

Well, the fix didn't last long. In fact the problem is occurring on a more consistent basis now. I haven't had the battery tested, but the eye is still green and I have NO starting problems or any other problems related to the electrical system. The battery isn't pulling an abnormal from the alternator or anything. It's just this lack of idle.

I have determined that if I drive with 2 feet just long enough to get to the end of my block (100 yds at most), it doens't stall. I can also sit there with it in gear and my foot on the break and rev up to about 2500, I'm good to go too. It seems that I have to put it in gear and give it some RPM and I'm ok.

Does this sound familir to anyone? Can anyone suggest a fix?

2000 Cherokee Freedom Straight 6 - 4.0L Automatic

I would next take a multimeter and see if the TPS has any electrical dead spots in it's travel.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Beer Gogglers wrote:

I have a bit different issue with my 88 4.0 but I've seen the behavior that you describe in several different cars over the years. It was most commonly caused by a bad or gummed up Idle Air Control. The motor and shaft would get gummed up or there would be a build-up around the port that wouldn't let the pintle seat just right. Usually, pulling the IAC off and cleaning it and the port in the throttle body would fix the problem. For some reason, I had to replace several bad IAC units in GM cars and they seemed especially prone to getting crudded up. It's something cheap and easy to try, at least.

My problem seems to be that the old Renix computer has a problem when the temperature is > Well, the fix didn't last long. In fact the problem is occurring on a

Wrong again Bill. See

Sure it tells the state for that one of the 6 cells. 12 volt batteries have 5 more cells that can go bad.

I had a delco with a green eye and still had 0 volts across the terminals.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Jeff Lowe wrote:

You are absolutely correct Mike, it is only one cell and FWIW, that one cell could still be open or shorted and indicate green, but my point is that it is a true hydrometer, not just a liquid level check. It is not a substitute for a voltmeter or a hydrometer in diagnosing battery/charging problems, but if it isn't green then there is something wrong.

L.W. (ßill) Hughes III did pass the time by typing:

enough

:)

Over 2 volts Bill. The green ball moves both by fluid level and specific gravity so it actually does test the fluid as well as letting you know when low.

Very much like the colored ball battery testers, remember them? It had X charge according to which ball floated at the top.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

"L.W.(ßill) Hughes III" wrote: