Well it just started last night and I'm not sure what it could be.It an 88 xj with the renix 4.0 in itand the problem is it revs up when I first start it and I have to shut it off then try restarting and so on. I just installed a homemade cold air in useing the stock box with the front cut ount and a few spectre 3'' fittings into a spectre cone filter. Since I had the rubber off the tb I cleaned it and when I went to start it reved really high and ran like that until I shut it down then restarted. I had a similar problem a few years back and it was the intake was loose but I check all the bolts and its fine, Please help. Thanks in advance.

 

you might try and adjust the tps,it will cause this,but you have changed a few things here so i would try that first and go from there.

 

before messin with your TPS pull out your IAC and give it a good cleaning with throttle body cleaner. or disconnect your battery and let the computer clear over night.

i know the problem but i cant think of the actual fix at the moment and im running a full on homebrew CAI with my renix.


BTW i assume you went over all your vacuum lines after you were done screwin around with everything? do you still have that stupid plastic vacuum tree?

not mine but ive put a red square round the thing im talkin bout, its plastic it gets old and cracks and can cause vacuum leaks which ive seen cause hi revs


and heres mine-notice the lack of vacuum tree

 

Search "tps" there is a ton of threads on the subject!!! I've personaly wrote to many of them! lol