Troubleshooting engine problem

Ok so in my two previous threads, I mentioned about a rough idling vibrating sensation coming through the entire comanche. I have eliminated a few other varibles and have figured out when the rough idling and driving occurs.

I start the jeep while the motor is cold, and it runs smooth and drives great with a bunch of power....Once it warms up and drives for a few minutes, it starts to lose power and runs rough...I have figured out that even when you start it after the motor has been off for 10 minutes or so, it will run smooth, but for a fraction of the the time when its cold. Could this be involving the open loop vs. the closed loop computer system? Perhaps involving the o2 sensor?

Thanks,

Alex

What year, what engine.

Normally you should keep a topic in a single thread.

Yea i know, it just seemed that my other topics went dead...It's an 87' comanche with the fuel injected 4.0

-alex

We had a somewhat similar problem with slowrider's MJ in Moab. First, we found a cylinder that wasn't firing by unplugging one wire at a time. I believe someone else made this suggestion in one of your other threads. A new plug wire fixed that.

Then someone noticed that the connector on one of the fuel injectors was not very snug. A little crimp with some pliers fixed that and the Jeep ran much better. Check the connectors on all of the injectors. Perhaps they could vibrate loose after driving a bit (??).

ok, perfect...how insulated should my pliers be to be touching the wires while its running? by the way, its so weird how its so random and tempermental...last night it didnt have a problem but it was idling higher than normal.