alright, so i just started college last week and i occasionally have to drive 30 miles to get there, i just did my head gasket over the past week to make sure i didnt damage the cylinder head. before i did the head gasket my jeep was doing something weird. it would be going down the hwy just fine and then all of the sudden it will kinda start to buck, the RPM drop anywhere from 250-500 RPM, and it really jerks. it only does it when im on the gas even when i maintain speed. i have changed the TPS, CKP sensor, and even the PCM and it still does it. im all out of ideas and i cant figure it out. HELP!!!

 

it might be a fuel issue... i've had that happen to my 93 p/u... but it was the wires/plugs/cap and it ran fine after that.

 

already did the cap, rotor, wires and plugs

 

wow nobody else?

 

Try checking the fuel pressure at the rail.

 

i did that when it first started doing this, it has at like 40 or so (cant remember it was 5 months ago

 

even if theres no check engine light codes should be checked

 

Fuel filter dirty.

Fuel pump "sock" dirty.

Fuel pump inadequate pumping under load.

 

fuel pump, tank, lines and filter all got replaced (at the same time) to be able to get it running back in December and i only run gas that has no ethanol. and OBD I doesnt store codes

 

Obd1 does store codes. Think your cat might be plugged?

 

sure does store codes renix does not

 

hmmm didnt know obd I stored codes, a plugged cat could be possible since i have been running no muffler for 3 months

 

Turn your key on off on off on in 5 seconds and the cel will flash. The number of flashes followed by a pause indicates the code. You need a list of codes though. Might be in haynes or chiltons.

 

Sounds a little like this story:

My 90 started all sorts of ruckus. The whole works. It would hesitate, miss, pop back out the intake. (the confetti blowing out the grille is how I found the mouse nest in the air cleaner). No start a few times. Run like a (frightened) ape if you floored it, but stumble on even throttle. Or run fine for days. Found that most of the usual suspects all seemed to be about $50 each, and some are a ***** to change. I didn’t want to just throw money I didn’t have at it, so I just did normal tune up stuff. Odd symptom (you may or may not have). Could start and run all day , no problem. Turn it off for 2 minutes then “the tantrums”. The sitting business really had me. Oil dripping around the CPS sensor, engine heat migrating to the coil or TPS or something? Something involving the manifolds and a vacuum leak? Catalytic converter. Had to be heat migrating while it was off. It took over a year to figure out that the heat shield over the manifolds was expanding into the injector wires at the front. I moved the wires, piece at last!

 

Check the ground on the TPS and the distributor it could either be out of time or loose, the knock sensor is a possiblity to.