ok, so my brother drove 1993 cherokee (4.0L Engine) down from flagstaff and said it was periodically loosing power, so I let him take my jeep back up to flag so I could fix his fuel pump...only thing is it wasn't his fuel pump. here are the symptoms, it takes 10 seconds or so for the engine to start, it just keeps turning over. Once it starts, it will only idle for about 10 to 20 seconds befor it stalls. Now if you start it and give it gas it will automatically stall. Also, when you drive it (which I can't anymore) it will just bog down, and it won't accelerate. It won't stall if you are driving, but it will not accelerate. so here is what I have either checked or replaced so far.

Fuel Pump
Fuel Filter
Throttle Position Sensor
I took the CAT off to see if that was clogged
I also thought it was the EGR valve, but they didn't put those in the xj till 1994

I am stumped! I hope you XJ Guys can help me out. Any input would be greatly appreciated.

Im at a loss. I thought of all the stuff you checked.

I wonder if it has something to do the with injectors themselves? Have you had them pressure tested to make sure they are putting out the right amount of fuel?

I know right, what else could it be? I don't understand

I have not had it pressure tested, I just have a hard time believing that it could be the injectors. I just don't see how they could go out or get clogged if the jeep is driven on regular basis. Do you think I have them pressure tested?

What do the plugs look like? Timing issue?

I havn't checked the plugs, but I know my brother replaced them about 6 months ago. And it isn't back firing so I don't think it is a timing issue

Are you smelling any gas. My car had something like that and it was an injector going bad and had to replace.

I don't smell any gas, but I guess I will check the injectors

How did you check the fuel pump? Or is it a new unit?

Has any work been done to the Jeep as of late? New lift? New parts? eng work? Did you take and vac lines off?

If my mechanic at work gets back i will ask him what he thinks.

The fuel pump is brand new.

No new parts, no rescent work.

I thought about a vacuum leek, but was kind of hoping it would be something else. Do you think thats what it is?

American 4x4 wrote:The fuel pump is brand new.

No new parts, no rescent work.

I thought about a vacuum leek, but was kind of hoping it would be something else. Do you think thats what it is?

I don't know... Based off what you said it sounds like a vac line or fuel issue...

American 4x4 wrote:

I thought about a vacuum leek, but was kind of hoping it would be something else. Do you think thats what it is?

Plus, even though it may be harder to find, Usually much cheaper.

haha crap...alright I guess I will try to find the leek

Talked to eric my mechanic here at work said to first chk fuel pressure 40psi+ you are good. He said to check your coolant temp sensor and also your crank sensor. He first guess was the coolant sensor but he said to check fuel pressure to eliminate a fuel problem

alright guys, I gotta some things to look at now. If you have any other ideas on what it could be let me know. hey also I am brand new, someone left a business card on my jeep so thats how I found you. I will keep my eye on the upcoming runs, and hopefully I can meet you guys in person

Crank Position Sensor was what I thought also, but I don't think it would start if it had a bad CPS.

any luck with your problem

figured it out, you guys are going to think I am so retarded! so one of the hoses on the fuel pump somehow popped off and was sucking in air not gas ...how i don't know, but I feel like a freakin idiot, and I replaced so much that wasn't even broke. that is life I suppose live and learn