Ok I'm stuck on this one so any help would be great. Its a 1997 Cherokee Sport 4.0 AW4 4x4(rest of my mods are in my sig). I just got my jeep back from the body shop(front end wreck) and now when I try and accelerate it is really slow. If I give it any more than half throttle the rpm's jump up and I can feel the trans downshift but it will not accerate very fast. If I drive with 1/4 throttle the trans will shift through the gears and go into OD but still feels slow compared to how it was. If I floor it from a dead stop it will still accerate slow and the revs climb slow. It will also not go faster than 60 even with it floored. It will rev fine in park and hit the rev limiter. It idles fine. I checked the trans fluid(when the jeep is warm) and it was fine. The CEL was on and I had it scanned(TPS code) The TPS was reading 17% at idle and reading 78% at WOT. So I replaced the TPS and I still have the same problem but the CEL is now off. I also checked and adjusted the kick down cable but that didnt help at all. Also I have replaced the cat and the muffler about a year ago so I know thats not the issue. Sorry for the long read just trying to explain the problem as best I can and explain what I have done and tired. Thanks in advance for any help.

 

I would check compression, find out if its an internal engine problem.

 

Have you looked to make sure the fuel pressure is ok? I know that happened to my 99 xj before it got wrecked. The pump wasn't able to keep up with my foot. Did you adjust the TPS? Iknow my 88 is adjustable. just a thought.

 

I havent checked fuel yet dont have my pressure tester at the house....The TPS is not adjustable so I know its not that....just frustrating......did your 99 not accerate....weird thing is even under load it doesnt break up just doesnt accerate.

 

My 99 accelerated like I was towing a battleship. 2 days later fuel pump took a dump. replaced fuel pump and voila! it run like a top. I would def check fuel pressure first and also replace fuel filter. I've been through 2 filters already since Nov. because of the dam winter blend.

 

Well that will be the first thing I check just wish it would run right cause we are susposed to get 10 to 15 inches of snow tonight

 

Check fuel pressure, spark, how old is your oil? What's your air filter look like? Check some of the major restriction points, also, if it's back from the body shop, what was the damage/what did they need to replace?

 

Air filter is brand new....plugs,wires,cap and rotor along with the coil were replaced about two years ago with all accel stuff...oil only has about 3000 miles on it. I use mobil one and a mobil one oil filter....the body shop replaced the front fendors, the header panel, the a/c condensor and radiator, along with the e-fan and the fan shroud....they didnt touch anything on the motor or trans....i drove it to the gas station today and had it in 4x4 and there was no binding or weird noises so I dont think anything is draging.

 

I have a 97 and after a couple of years the rotar seems to gum up fast I'm guessing from letting it idle.
Up here long warm up is common due to -30's

 

Fuel Pressure really needs to be checked, you will be able to rev the hell out of it under no load but when you try and drive it will bog like a fat kid running a 5k.
Start and warm engine and note pressure gauge reading. Fuel pressure should be 339 +/- 34 kPa (49.2 psi +/- 5 psi) at idle.
If engine runs. but pressure is below 44.2 psi , check for a kinked fuel supply line somewhere between fuel rail and fuel pump module.
If you were in a wrech look for bend fuel lines.

 

Thanks for the help guys....When I go to work tommorrow I will be able to get my Fuel Pressure tester and thats the frist thing I will check when I get home.....Everything I have been reading is pointing to that...the pump is 14 years old and has 160000 miles on it

 

Good mornig,

I have the same problem in my Cherokee XJ 1998. I would like to know how to adjust the cable from the kick down on my car because on the "first stick" I feel that it is very slowly (don´t have enough power).
I´m from Brazil, and here is very expensive to fix it at the expert mechanic, so I want to do it by myself.
Thank you all. Michelin

 

hey were you ever able to find the solution to your problem?? because my '97 Cherokee 4x4 is doing the exact same thing you described! thanks.