98 XJ 4.0L 4wd No CE light

I am trying to narrow down issue with the engine sometimes bogging down when i put it in reverse or drive (bogs down to around 250 sometimes). It doesn't happen all the time and has never died on me. And my normal idle is not steady. Jumps from 700-1200 when in park, Again not all the time.

Would a faulty CPS cause this and possibly not throw a CE light.

Cap, plugs, wires are good

Thanks

 

Yes, could also be IAC or TPS.

 

TPS would be my guess. Since its runs and doesn't die when your give it gas, its not the cps.

 

Still could be the CPS, those were my symptoms before I replaced mine.

 

Thanks
But how could i test these sensors to narrow it down

 

Check this out, it should help with testing your sensors just have to find the right page http://www.lunghd.com/On_Site_Tech.htm

 

Thanks and Awesome site but i didn't really see any thing in there to test the cps or tps. That site also deals mostly with 84-90 model xj's. Not sure if the same info would pertain my 98.

Any other ideas

 

Did you happen to find out what happen to your xj?

 

Actually i haven't. Kind of put that issue to the side and deal with it every time it happens. But i can say it has been so long since it happened, i cant remember the last time. Hopefully if fixed itself

 

Nice!