should i just get a new motor???

[old_man]

I didn't even think about the gap since I run high energy coils on all my other stuff. IIRC the gap should be .035 but even a large gap shouldn't cause what he is seeing.

An old trick to check for a plugged cat is to wait until it is happening and then pull the O2 sensor for a minute to see if the problem gets better with a bypass route.

 

[JeepZiggy91]

no compression test yet. i am gonna stop by one of the auto zones in town after work tomorrow and see if i can rent their tester along with the fuel pressure tester.

gap was at .35 on all of them but number 6 that was at .37 i adjusted it back.

what does ccv stand for?

and i have no cat, havent for over a year now and it ran just fine until about a month ago.

 

[stroked88]

sorry I left out the question mark behind it. I was asking if you had replaced it? crank position sensor. NOW stop being an a$$wad. I typed CPS cause everyone know what it means.

cps usually causes a crank but no start condition. maybe he's a noob, not every one knows what it means.
and ccv stands for crank case ventilation. it lets the pressure build up out of the crank case escape into the intake. I think you need to try the search function, go into advanced search and search titles only, check the stickies and there is a guide to searching

 

[JeepZiggy91]

cps: crankshaft position sensor. i know what that means. im only half retarded. i ruled out that because it was running and i assumed it was a fuel mixture or something with the fuel system sensor because i could smell it running rich and it didnt do it all the time, just most of the time so i figured if it was mechanicle it would happen ALL of the time.

 

[JeepZiggy91]

had a long couple of days but i got the compression test, gonna do it tomorrow after work. reattached a vaccum line that's been pluged for over a year and just like every other time i changed something, it ran great for a couple of hours and then back to crap. it is running/ sounds like when you get water in your intake...

 

[JeepZiggy91]

compression results:
1:105
2:110
3:105
4:105
5:115
6:100

 

[dj's 2000 xj]

Check the cps wire, I had one that burned the insulation and caused a problem. Otherwise, i go with clogged injectors/bad fuel pump type problem. That is based on my past experience. The only thing is when my 2000 head cracked I got some weird action before complete rebuild.

 

[JeepZiggy91]

well if something was going on with the cps it would be a no crank problem not an on again off again thing... i just replaced my sending unit and fuel filter so i know its not that. ive ran a few different injector cleaners but i decided that this weekend im gonna soak them overnight in some heavy duty injector cleaner i have.

 

[joe_peters]

well if something was going on with the cps it would be a no crank problem not an on again off again thing... i just replaced my sending unit and fuel filter so i know its not that. ive ran a few different injector cleaners but i decided that this weekend im gonna soak them overnight in some heavy duty injector cleaner i have.

The crank position sensor--CPS or CKP--and the synch sensor--CPS or CMP--have nothing to do with crank/no crank problems. They do, however, have a lot to do with run/no run issues.

 

[bluejeepkid]

the jeep runs, its not the cps! plz stop suggesting that. the jeep has intermittant stumbling and popping and loss of power. it will idle normal, but as soon as you give it throttle it imediately loses power and stumbles.

 

[JeepZiggy91]

thank you andrew

 

[bluejeepkid]

lol no problem

 

[JTieman]

Get a new ignition control module, replace it. If that doesn't fix it take it back. It may even test good but may be completely toast.

I had the same problem, everything turned out to be fine, except the ignition control module would all the sudden heat up and then I would have horrible spark, missing and popping/backfires. One day, it just completely gave up the ghost on me. That was it. Exact same symptoms you describe.
:firedevil

PS: I hope you didn't have this part in your list, otherwise please disregard!

 

[JeepZiggy91]

no it never crossed my mind. im broke till next friday but ill defenetly chech that out. thanks

 

[winterbeater]

compression results:
1:105
2:110
3:105
4:105
5:115
6:100

Your compression is at the point where it may be a problem. I've seen other cars (not XJ's though), that wouldn't run with this low a compression. I've also seen people on this forum report even lower and claim to run good.

IMHO, the mechanical ability of your rings and valves is near the end.

 

[old_man]

the jeep runs, its not the cps! plz stop suggesting that. the jeep has intermittant stumbling and popping and loss of power. it will idle normal, but as soon as you give it throttle it imediately loses power and stumbles.

While what you say is normally true, I actually had a cps that started and idled just fine. Sometimes it worked fine and sometimes it worked fine until about 1500 rpm. Then it would start dropping pulses and everything got screwed up.

I say that so that if a spare cps is at hand, I would do a swap since nothing else is really making any more sense than that.

 

[bluejeepkid]

While what you say is normally true, I actually had a cps that started and idled just fine. Sometimes it worked fine and sometimes it worked fine until about 1500 rpm. Then it would start dropping pulses and everything got screwed up.

I say that so that if a spare cps is at hand, I would do a swap since nothing else is really making any more sense than that.

i have a spare and i guess it wouldnt hurt to try. someone else suggested the ignition control module?? i dont understand how that would cause those kinds of running issues:dunno: