jgstang

new problem.. the jeep runs great now but! every once in a while when i'm driving it, it will have some good jerking going on and then run good again. thought it might be the fuel mod again so we warrantied it and still does it ? will not drop a code.. thanks

BlueRidgeMark

1. Stop throwing parts at it. Test.
2. Could be a loose wire which is killing your ignition. On a 97, do you have a coil? Or coil packs? If you have a coil, check the 12v feed wire into the coil. My 97 Cherokee 4.0 acted like that due to a bad connector going into the coil. It gradually got worse until I found the bad connector.

jgstang

Oh i know, and yes it has a coil just below the battery... I did the new parts awhile ago and its been running great for some time now.. the problem started when, well lets say it was a bad life changing day for us and i left the phone on the charger in the jeep for a few hrs.. so the battery was very slowly drained and after being jumped it took a couple days for the computer to get back! other than the here and there jerking it runs awesome ? starts right up,lots of power, runs smooth and decent mpg.. i just replaced the fuel mod because i could for free, and about a year ago we broke down on the fwy when the jeep started jerking and just quite and it was the fuel pump..

BlueRidgeMark

Could be the connector or the wire.

jeepdewd

This was a problem for me at one time and got so bad that my cat and muffler exploded while driving... when I say exploded, the honey comb in the cat was completely gone and the muffler blew completely apart. It was a domino effect that continued to get horribly worse. I had what they called a dying jeep and it usually starts with your symptom your having.

The cheapest test you can do is get connector grease and stuff in all the little ports on your harnesses that connect to your pcm.

If your problem vanishes for a while you know what to look for

Harnesses will need repinned, and while that's going on you want to test all the wires because there are likely some wires that are corroded to the point they need replaced.

I spent about 2500 with a mechanic trying to figure that out.

If your problem doesn't go away try testing what the guys above mentioned, if that doesn't work you maybe looking at opening your motor to replace your valves. When you release the springs and pull the valves and one or all of them seem a little tight while pulling then those are the ones you need to replace, but bad springs, push rods and or lifters could be causing a valve not to open all the way creating some misfiring which has the same effect of the jerking your getting

About three years after my electrical work is when I started to get a jerking again and finally after two years I started getting miss fire codes. New cam sensor, cap, button, wires,plugs, coil,injectors, fuel rail was cleaned... there wasn't much after that but the innards of the motor. I found a bent valve (tight pulling it out) and replaced all my spring push rods and lifters. Jerking, gone.

Unfortunately the day after I got it back together i spun a bearing and destroyed my crank shaft.

Now my motor is back open and I'm working on disconnecting my trans so I can drop my crank

Jeep apparently is an accronim for just empty every pocket.

Rockauto.com is where I get my parts, I make under 40k and it barely effected my budget. My jeep only takes my time.

I hope you get it figured out dewd!

jgstang

update! took the coil off and bent in the 2 prongs slightly and so far after 80 miles or so runs fine..

BlueRidgeMark