Page 1 of 1

2002 Jeep Liberty - Misfire FIXED

Posted: Fri Jul 10, 2009 5:26 am
by alvinss18
This one is killing us.

We have have a 02 Jeep liberty 3.7. This was brought to us from a transmision shop that just rebuilt the tranny. The complaint was running rough. We checked spark and fuel, both are there. Found radiator blowed out. Ran compression check. Found no compression on three cylinders. Removed the heads and sent to the machine shop, it had three valve seats melted. Reinstalled heads and started. Vehicle ran rough but ran.
This is were it gets tricky. Now we are showing no injector fire on Three cylinders, the same that had the valves seats melted. We had injector pulse before we started this escapade. Trace it back to the computer. Install a new computer and reflash. Vehicle started and ran rough, not as rough, but rough. Found cranksensor loosing synch. Replaced crank and cam sensor. Vehicle will not start now and is showing a secondary code for a ignition coil.
Anyone have any ideas?

Re: 2002 Jeep Liberty - Misfire

Posted: Sat Jul 11, 2009 2:10 am
by steven kiser
melted or damaged seats = cylinder failure.

Re: 2002 Jeep Liberty - Misfire

Posted: Mon Jul 13, 2009 8:14 am
by Stewart Levy
So ? any fix or did it fix itself?

Re: 2002 Jeep Liberty - Misfire

Posted: Mon Jul 13, 2009 8:29 am
by alvinss18
No not yet. Don't think there is a cylinder problem, we checked those pretty thorough. Got my man checking the timing marks again for the 3rd time. I don;t think that is it, just by the codes that keep coming up.

Re: 2002 Jeep Liberty - Misfire

Posted: Mon Jul 13, 2009 8:32 am
by Stewart Levy
What scannner are you using. Can you read the ECU in live time!

Re: 2002 Jeep Liberty - Misfire

Posted: Mon Jul 13, 2009 11:23 am
by alvinss18
Tech found it out of time by two teeth. Starting but running rough. Moved two of the fuel injectors that were at the valves that melted, and misfire moved with them. Got two injectors coming in the morning.

Re: 2002 Jeep Liberty - Misfire

Posted: Tue Jul 14, 2009 2:18 am
by steven kiser
sonds like this will need prayer candels and pixie dust when this finally leaves. :lol: :lol:

Re: 2002 Jeep Liberty - Misfire

Posted: Tue Jul 14, 2009 3:02 am
by alvinss18
At this point, I just want it fixed and gone. I already lost $$$. You try to trust your techs and their abilities, but these are the situation that gives you doubt. My guys are normally great. We had the timing discussion before he got into a "throw parts at it " method. It is my fault for letting him talk me into it.

Re: 2002 Jeep Liberty - Misfire - Fixed

Posted: Tue Jul 14, 2009 10:22 am
by alvinss18
Fixed and running like a champ

Re: 2002 Jeep Liberty - Misfire FIXED

Posted: Wed Jul 15, 2009 2:35 am
by steven kiser
as an owner i'm guilty of that as well. it kinda goes with the territory. i have to rely on my techs. if i second guess them they'll start not making any diagnostic decisions. they'll wait for me...............................