i have an 88 xj 4.0l auto from an idle it has a hesitation when u accelerate. ive tryed adjusting the tps and put a different one on and adjusted it to specs and it still does it. is anyone having the same problem? thanks for any advice u can give me.

 

my roomates 88 xj does the same thing, apparently for his xj its the tranny... try flushing out the old fluid and topping it off with new tranny fluids

 

well its funny u say about the tranny cuz mine doesnt shift it just stayes in first gear . so i unpluged my tcm so i could shift it manually. could that be my problem? do u know how to fix it?

 

cant help you there, sorry bud

 

My 88 had a hesitaion too. When I pulled the motor out to replace it I found that I had 2 bad injectors.

 

The hesitation could be a clogged fuel filter. It needs to be replaced every year. My buddys jeep had hesitation and the new $12 fuel filter fixed it. As for the tranny not shifting it could be the throttle position sensor. Its attached to the throttle body. My auto wouldnt shift until 4500 rpms and it turned out to be the TPS. Good luck

 

the PO already did the tps so i would try the iac, that could cause the issue too, its right next to the tps on the throttle body

 

i replaced the tps and adjusted it to spec i havent tryed the iac but i will.coud the iac be taken off and cleaned or does it have to be replaced?

 

does anyone know the correct way to adjust a tps. if so can u please help me by telling me what the input and out put volts should be. im thinking im doing to wrong. its a 88 xj 4.0L auto. thanks ahead of time.

 

you cant it goes in when the throttle plate is closed and it reads between 0-5 volts they or .5-.4.5 volts just clean the throttle plate with a tooth brush and intake cleaner just a bit and put it in!

 

should read somewhere around .5-.7V at CT and around 4.5-5V WOT

 

that was the reading i had and it didnt fix the hesitation from idle and ive been told that my tps controls my trans shifting and when i adjusted it to what u just said and it didnt change anything with the trans. anone have any ideas. im stumped.

 

clean the throttle plate and check for vacuum leaks

 

You should also adjust that throttle cable that goes to your tranny...

I don't remember exactly what it's called, but theres a button on the top of the housing, you pull the cable sheath back while pressing the button. Then you step on the gas to WOT to adjust it properly. When you look under the hood again, it should have moved and locked into place.

BTW, I went thru four new TPSs before I got one to work. Yes, I adjusted all of them properly.

 

Here's a link:
https://www.cherokeeforum.com/f2/aut...00-rpms-11008/