james750

got 2 xjs from southern co and my mj, NO RUST, one of the xjs was infested with gophers though :eek:

talked to a mechanic this afternoon about my problem, he seems to think that the problem is in the wiring to the IAC motor. thats the next thing to check.

This should be stickied.

3.43

one more question, will coolant spill out when i remove that sensor?

ok, just wanted to make sure that that wasnt a symptom of this problem

ok, so thats what it does 90% of the time, starts up, goes up a little bit then instantly goes back down. but once a week or so, it stays at the higher idle.

ok, ive been out checking the other xjs and they seem to start up and immediatly go to normal idle. mine (has always) starts up and revs a little bit b4 immediatly calming down, i didnt realize this wasnt normal until it was getting stuck at the high idle. So is it normal with the Renix, or no? 135, i actually didnt get a chance to mess with it b/c i had to leave the house again and didnt have enough time to let it cool again. more tonight, its parked and ready in an hour or so.

while waiting for the engine to cool down, i decided to go on over to NAPA and have them look up the Air Charge Sensor, wasnt in their computer either. :hmm: Looks like if the CTS doesnt work ill be turning to BLHTAZ for the part. :typing:

chico, i feel like a moron, ,i went and checked and the TPS was unplugged! :oops: ok, so new IAC is in, now its time to wait and see if this fixes it, though i don't think it will b/c i plugged the old IAC back in and it seemed to run like it did with the new motor. CTS comes tonight, that is if i can get it out.

:headpop: i put in the new iac and now whenever i press on the gas it tries to stall b4 revving up. Any thoughts!!!!!

ill try.

News from el garaje (garage) come to find that the last owner rounded the head of the CTS and therefore i can not get a wrench around it. :mad: So I am currently trying to figure out how to get the CTS off. maby more tomorrow, i decided it would be easier to return/replace IAC motor first and see what happens

' Ive never seen it in Denver, ill be at the flea market next week and see.

well, today on the trail it did it once, so problem not found. :headpop: But the MAP did lower the constant idle quite a bit so no wasted money there. its just hard to diagnose b/c it only does the high idle on startup once a week or so. Over to carquest tomorrow to pick up the CTS, then comes MAT, if it continues after that I won't know what to do, ill exchange IAC also in case i got a faulty one.

WOOT, new map has helped a ton. it now idles really low and when i start it up it is more normal. :D

MAP is replaced!!. while i was under, i found a disconnected vac hose :eek: , i reconnected it and so far everything seems ok, but its kind of hard to tell b/c it only did it one day this week so far. Tommorow the CTS comes in and ill replace it, but it sound like a bit of a PITA; :headpop: We'll see if that fixes it! EDIT:checkers said that there was no MAT in xj or mj.

I already replaced the IAC. I'm going to run up to chker and pick up a new MAP, MAT, and CTS and see if replacing those fixes it, I'm a little desperate to get it running b/c of a trail run i am going on Sunday.

sounds EXACTLY LIKE MY PROBLEM, btw, on that wikianswers, there was mention of CTS causing the problem too.

It did do it after warm for a while until after i replaced IAC, then it stopped for a while, and now it does it on initial startup, then stops until I start it up again. yeah, i didnt know what the speed stepper motor was to tell u the truth, it was just a recommendation that i found on wikianswers for someone with a similar problem.

could it be the idle speed stepper motor? on initial startup it revs high and goes back down and doesnt rev up high anymore.

well, last night it did it once in conifer. Idk if the oxygen sensor, It only does it on initial startup. and oxygen sensor would cause idle problems whenever at a full clutched stop, right? Ill try picking up a MAP sensor tommorow. if it doesnt improve, ill change IAC, then oxygen i guess.

what years were the cps' hardwired?

bringing it back, uggghhh!!! :headpop: So its been running fine since last update, until TODAY. I went to Denver to put the topper back on and it had the same problem where it would rev up high for about 10 secs, then calm down, came back to conifer, and the problem went away again. Is it related to temp(much hotter in DEN today) altitude (5000 Denver 8800 Conifer)? what it does when i consider it running normal is starts and goes to around 1500 rpms for a split second after start and then goes back to normal idle, bu t i know that our other xjs don't do that, so it may not be normal. Could it also be a defective new IAC? don't think it is a vac leak because it calms back down after a few seconds.

Thanx for the info Eagle. What year did they start using the Check engine light? I know that my old 92'xj had it... I am just realizing now that i learn more and more everyday on these forums.ive learned more about the mj in the past few months than i ever new b4.