HI, i just got into the jeep thing and having a little issue with my 1990 jeep cherokee. it has the 4.0 l engine 4x4 and a 5 inch lift and 33" tires. i wanna go take it down some trails this weekend but havin a problum with the running condition of it. when its cold it runs better. when it warms up it has this poping in the intake. and once it warms up and i shut it of it has a very hard time starting back up and when it does start it runs wicked bad untill i almost redline it then it clears up. and its mostly on low rpm's high rpm's its fine

PLEASE HELP ME
THANKS
John

 

Sounds like your ignition timing is off which will cause both of the symptoms you have.

If you have a timing light i would check that and reset the timing.

My guess is that the timing is retarted about 5 degrees maybe alittle more.

Check you cap and wires to make sure there in good shape and also make sure the wires are in the correct order.

 

Alright ill give that a try. do u know how to adjust the timing on these and where is the timing marks and whats it soposota be set at.

 

Let me go check my manual just clip 1 end of the timing light to the #1 ignition wire and the timing marks will be on the crankshaft pulley.

i'll go check the specs now.

 

Ok well my scanner is not working right now to scan the manual for you so here's a link on how to replace the distibutor and how to line it up when your done.

Just scroll down past the removal and installation part and read the how to time the distibutor, this will have all the info you need.

http://www.justanswer.com/questions/...kee-laredo-4-0

 

ok thanks ill give that a try a and post my results

 

ok here is my results on this.... i was checkin out the distribtor when i noticed the bolt that holds it was loose so therefor the distribtor had all sorts of free play. i tightened it up and its better now but still has a hesitation under accell then clears up at full throttle, it almost seems like a clogged cat or suttin. has anyone encountered that in a jeep. and the emmision matiance light is on, is that like the check engine light?? and how do i check what it is thats makin it go on

 

Did you check the timing? or just tighten the hold down?

 

did you find out what was causeing this ? im having the same exact problem

 

sorry i took so long to respond back i havent had time at work to go on the comp. but i didnt check the timing on it from what i know the timing is not adjustable, and i dont realy understand how to check if its on, and i got another update, it started running crapy doin the same thing and so i decided to change the distribtor and its still the same. im so lost with this and it seams to be jus gettin worst and worst. does anyone know how to check codes on them maybe that will point me in the righr direction. the emmisions matiance light is on

someone please help me

thanks

 

My understanding is that if the cat is block, it will bog down under more throttle (more exhaust trying to get through smaller holes). I would check your TPS (trottle position sensor) Fairly cheap part through autozone, some may say get a mopar brand, but I've got an autozone one and haven't had any problems.

 

ya thats what i know about a cat bein clogged also but this problum is jus so weird and iv never herd of it lol, i put a tps sensor in but i got it outta the junkyard jus to test mine. it prob had the same prob as mine. another thing is how do u set the tps. i know its soposota be .8 volts when closed but what wire do u test and what should all the other wires soposota be at for volts. does anybofy have a wiring diadgam or anythin of that

HELP MEE IM LOOSING MY MIND WITH THIS JEEP

and another thing is im gettin no heat outta this thing its warm then just fades to cold and i put a t stat and water pump in already it there anythin special i should know about when tryin to bleed the coolent????

 

CHECK your Fuel pressure with a gauge on the fuel rail. I had an almost identical issue with my 90 XJ and believe it or not it was the little piece if tubing in the tank on the fuel pump. It was rotted and I pulled it off without loosening the clamps. If you have less than 31psi, check the pump. Nice thing about the Renix era, you don't have to drop the tank to get to the pump.



And I went through every sensor and anything else I could find. Lucky me, I had a complete parts XJ to move parts around with, and now I have a nice spare parts box to carry...

 

ok ill try that out this week simetime and ill let u know and post my results thanks

 

not sure if you fixed this yet , but i had the same issue and i replaced my pump today and it seems like a whole new jeep , my pressure reg filter and pump are all one unit so i cant be certain wich one exactly is was