OK, now I really have a problem with my new JK. It's a 2010 with 3000 miles on it and the problem started soon after I got it.

The Jeep starts every time on the first attempt. It doesn't crank long and there are no strange sounds or clicks. However, after running stationary for about 1 second, the engine dies. I restart, it runs, and dies again after about 1 second. Some mornings I have to repeat this six times before it keeps running.
This can happen again after driving a short distance. But when the engine is hot, it's fine.

Two days ago I was sick of it and brought it to the dealer. They said there were no updates or flashes for my VIN. They checked wires etc, couldn't reproduce, and I had to leave it overnight. The next day I was asked to bring the spare key. They probably did something to the chips in them and said the problem would be fixed now. It isn't. So, I'm going to keep bringing the JK back until fixed permanently.
Problem is, it's 1,5 hours round trip to the dealer, the JK is my only 'car', so I have to rent a car every time ... I'm hoping someone here can help!

Some things I tried/thought of myself:

• Different brands and grades of gas
• JK is garaged in SF Bay area, it's pretty warm & dry here
• JK is parked level
• Put transmission in Neutral, then start - no luck
• Pump accelerator pedal several times before starting - no luck
• Raise RPM slightly after starting - engine still dies unless I rev the hell out of it

 

Sounds like a key issue with the security system. The wcm/skreem module.. Its under the plastic around the column.. U might try unplugging it and re plugging it in.. It's got a red lock so be careful.. Either way u should take it to the dealer..

 

Is there a code stored?

Another thing to look at is the cam position sensor. If it is loose or otherwise bad, it will cause the ignition to shut off.

Because you mentioned it is fine when the engine is warmed up, and the dealer has already reprogrammed the keys, ask them to troubleshoot the cam position sensor.
The spacing on that is critical.

 

After 3 times with the same problem it qualifies for Lemon Law here in the great state of Michigan. I would check with the law in your area and get cracking on it. Just google Lemon Law Lawfirms. They will get Jeep to take it back and refund your money and you can get a brand new one

 

this issue sounds a lot like a SKREEM / WCM issue...

one thing I would try is using the spare key instead of the normal one for a few days and see if that helps.. if it does it will mean the transponder in the one key is defective...

the cam position sensor usually wont let the jeep start at all...


the SKREEM / WCM allows 2 seconds of run time and if it doesnt see the proper signal from the key, the jeep will shut off..

the WCM also handles remote keyless entry... if your WCM has a loose wire or is not plugged in properly, your remote keyless entry will not work... if your remote keyless entry works then your WCM is active on the CAN bus and connected properly,, chances are at that point it or the key is likely defective..

the transponder signal from the keys is very weak signal... if the WCM antenna is not perfect it will be hit or miss...

-Christopher

 

Yeah, the skreem/wcm could be the issue, but the keys have been tried, and it is ok when the engine is warm.

I'm just tossing up other ideas.
Can't disregard anything until it is diagnosed.

 

may not be the engine is warm so much as the WCM itself is warm.. electronics issue often manifest themselves at various temperatures...

-Christopher

 

OK. I give up. It can't be anything else.

 

Haven't looked at the fuel system to closely on the JKs so I just know and can't do it right now so I have to ask you to look. On some vehicles there is a fuel pressure regulator on the fuel rail. Have seen the regulator go bad and let the fuel leak out of the fuel rail and when it does it will sometimes cause what you are describing. The regulator is usually a silver colored round looking device and may have a vaccum line attached to it.
A way to check for fuel being the problem is to cycle the key on for about 10 seconds and off two or three times before attempting the first start. If after doing that it starts and runs fine then it is draining fuel out of the fuel rail over night.

 

Interesting. I'm curious to hear what's causing this problem.