88 4.0 auto, etc.

So, I had this problem originally where I wouldn't be able to go more than 55 on the highway, didn't want to accelerate, and it sure felt like something happening with fuel, as the only time that I remembered it before was when I ran completely out of gas once. Shaking if I accelerate very hard. So it did it again, and I thought it was for sure the fuel pump. Changed it, it was fine, for awhile. Before that I changed the fuel filter.. it was full of crud.
Getting ready for a trip, I had a can of sea foam so decided to run it through the throttle body, then the rest 1/2-2/3 of it in the gas tank. Now, 300 miles later, it's doing it again. I took off the fuel filter and it was full of nasty thick crud again.. Thought that was weird... So I put a new one on, and it ran good for 5 miles. But then I went to get on freeway and the problem arose again.

My hypothesis is perhaps that the sea foam knocked a lot of crud loose and it is clogging up the pump again... Maybe I should find a way to get the tank down and clean it up? It seems weird that 300 miles later there would be a lot of brown stuff in the filter again.

Any ideas? Maybe it's not fuel related???

Cherokees are supposed to be good vehicles. This pisses me off like none other...!

 

I vote on a cruddy fuel tank.

 

Hopefully I can get this sorted out before my next trip, thursday. If it is really gross down in there, do you think the fuel pump will be gone bad again or maybe just the filter should be cleaned out?

 

x2 sounds like maybe someone got mad and dumped stuff in the gas tank or something.

 

Just clean the fuel pump when you pull it out to drop the tank.

 

x3 Do you have a lot of enemies?

 

Hahah.. I try to be peaceable. You never know though, my neighbors are d-bags.

 

Alright. Fuel crap ruled out. Still does it...

It idles beautifully. Just when accelerating/put under load, it doesn't want to go. Sometimes if it is trying really hard, there will be a "clunk" noise from somewhere behind me.

Anyone? I'm tired of working on the jeep just to make it run.

 

Are you leaving your e-brake on?

How are you drums looking? Locked up perhaps?

Rear diff in good shape?

Did you pull the tank? It's not very hard to do.

How many RPM's can you get up to while in neutral? Only happens when you're driving?

 

We didn't pull the tank, but pumped out almost all the gas and had good flow, looked alright, filter 1 day old had no crud in it, pulled the pump out and the sock wasn't plugged up or anything... lots of pressure at the fuel rail.
We put fresh gas in, and it still did everything mentioned.

E brake is off, doesn't feel like a drag, but rather it will start speeding up then all of a sudden lose power. Like the transmission doesn't continue to pull through. Or something.

It can rev all the way to full throttle in park, haven't tried it in neutral but would assume it is the same.

What are drums? Brakes?

I haven't looked inside of my rear diff (dana 44), but the outside looks fine?

 

sounds like you are not getting lockup (overdrive) but then again in my experiances it will just keep tacing up in 3rd gear. idk. check the transfluid? is it low? is it dark? does it have little metal flakes on the dip stick?

 

It's dark brown but full - Just checked, no metal flakes in dipstick.

It's not just when going fast. It could be any steep hill trying to keep speed, or even just accelerating 0 to 35 trying to keep up with traffic. Until I get it fixed, it is doable but I get flipped off a lot

 

Dark brown is burnt fluid. It is supposed to be a somewhat bright red. Change the fluid and filter and see if that helps.

 

Aha!

Breakthrough. Upon recent discovery, it revs up in neutral, but if held at high rpms, it is starved and dies. So this is somewhat relieving in that we are not looking at transmission problems. That clunk I heard was backfire ( I think).

We're back to fuel, I think. ANyone want to comment on that?

I think the guys at napa sold me a bad fuel pump. The second I put it in, it started humming and has been getting louder and louder, and shakier since then. Right now it is not a constant hum, but rather a morse-code type of noise that fluctuates.

We completely blew out the fuel lines with air compressor yesterday (so it is not a blockage).

 

Pump should be under warranty. Take it back.