Hi all,
I bought an '88 Jeep Comanche (EFI, 4 banger) just to use it as a beater truck. Here's the problem, It acts like it's running too lean. It will start up and barely idle, and when throttle is applied it kinda spits and sputters until it stalls out. Sometimes it gets so bad that when I apply throttle it instantly stalls. If I partially block the air intake with my hand, it will rev and idle great. Is there anything I can do to fix this? It has no exhaust after the headers, could it be a back pressure problem? Could I rig something up to partially block the intake or is this asking for trouble? Like I said, this is a beater truck, so I'm not apposed to rigging things up just to make it last a few more miles. Thanks.

 

you may want to ask the people in the jeep section. they can help better.

 

huh, never knew there was a jeep section, I guess I only pay attention to the ram and dakota forums. Thanks.

 

ok im just gonna put this IN the jeep section for you

 

Well, you are definitely short of back pressure, grab some pipe and a cherry bomb I guess. But the way you described it it also sounds like you have a fuel pressure issue. Try changing the fuel filter, see if that helps, cheap enough to try it anyway.

 

lets get serious

EFI means there is a computer - they do NOT like "rigging"

this is a off road only - no plates? will give us big picture.

I think someone mentioned fuel filter already, start there, if you can fuel pressure will be helpful- often can get as a loaner tool at parts stores..

look for a vacuum leak- spray some carb* or brake cleaner at suspected leak areas- intake manifold, throttle body base gasket- vac lines and fittings- a change in rpm would indicate a leak-

I don't how you could live without a muffler- all that noise -

*never use starting fluid.

 

This is a strictly "off-road, run it till it dies, beater truck". No plates, no glass, no lights, no doors, no nothin. There is a cherry bomb muffler, but I doubt it generates very much back pressure, so I'll look in to the back pressure issue. I'll check the fuel filter and pressure too, it seems easy enough to do. Thanks again.