ajwill88

i have a 90 cherokee i just replaced plugs wires rotor and cap air control sensor it just started running rough and sputtering when driving anybody have any suggestions

XJ BoSS

Did you make sure the plugs were gapped to .35? You check the firing order? Sounds just a misfire

BigzXJ

This may not be your problem but its something you should check. Had the same problem. I checked, rechecked, and pulled my hair out. And this was my big mistake. I bought this 90 with a blown motor and dropped a 95 4.0 into it. Well long story short the 90 spark plugs are shorter then the 95. Got the right ones and idles smooth.

ajwill88

I have checked and rechecked the plugs wires and firing order someone had told me it could be the Cps . Is that a possibility

caged

no, it won't be the cps.

but, funny thing, my 90 (with a 95 motor 4L) just started doing the same thing.
so i did the obvious, new plugs, wires, cap, rotor, fuel filter and oil change and it didn't change a thing. plugs gapped at .35 and all ordered for the 95.

so, i'm watching this thread.

i'm thinking try cleaning the IAC motor, that's what i'm gonna try next... then maybe seafoam.

ajwill88

i just got done changing the throttle position sensor and it helped it running but it still dies out when you punch it from a stop

cruiser54

Is the TPS adjusted properly or did you just install it without adjusting it?

BigzXJ

I re-read your first post again. You said you change your air control sensor. The one on the throttle body correct?? You could have cracked a vacuum line when installing it?? Did you clean the throttle body before installing it?

ajwill88

yea i had to adjust the tps like 5 times until i think its bout where it should be. I had a friend of mine do a pressure test on the vacuum lines while i was at work today he said they all tested fine.when i installed the air control sensor i cleaned the throttle body with carb and choke cleaner before putting the new one on . it still bogs out when u get on it from a stop but it runs alot better

ajwill88

this weekend im gonna try replacing all of the injectors to see if that helps anything

cruiser54

What method did you use to adjust the TPS?