New2Jeeps42

Hey guys. I have an old 87 xj laredo 4.0 auto 4x4. When i first got it, it needed alot of work here and there, but i was driving it around anyways. One day, right after i went and filled it up with gas, it started bucking, hesitating, losing power. Then the thing died. It died because the alternator went. So i had that all replaced, and it never did it again.
UNTIL just yesterday after a month or two, after i just had it tuned up, new filters, all that. I went and filled it up at the gas station and left it idling outside my local bank, when i came out, it was sputting and losing power while idling. So i drove it around, as it hesitated when i would hit the gas, like it was not getting fuel, and then all of a sudden it would get it and the rpms would hop up and it would finallly accel. I drove it to the store and popped the hood and watched it. i hummed and hawed. then i shut it off and went to the inside the store, and shopped for several minutes. Got back in the car and she drove home fine as can be.
That night i had to go see family, and i had to stop at the store on my way. So i left home and it was running great, turned it off, went to the store, came back from the inside the store and it drove horrible all the way to my familys cabin. Hesitation, no power. Then much later, from the cabin home it drove fine.

It really seems like its being starved of fuel. I just had the fuel filter changed. Im wondering if it could be the fuel pump? or perhaps the brain?

The only problems i know of that it experiences is blowback in the air filter. could this somehow cause power loss and hesitation? I really need a new "air inlet fitting" like from this picture


but can find them nowhere at autoparts places

XJSETH

possibly clogged cat? when my exhaust manifold was cracked it did that all the time. also check your O2 sensors they might be bad too. or bad fuel pump/fuel filter.

Abovetimberline

If you can attach a fuel pressure guage to the fuel rail and check it,it should be around 30-35lbs,from my own exsperience I had the little rubber hose in the tank loosen up which caused this problem except mine was worse,it only ran at wide open. I.A.C can also cause this if it is starting to go out. One other thing you can check is the egr.

New2Jeeps42

how much does a fuel pressure guage cost???

i drove it again this morning with three stops, one was a gas station. it ran fine.