this just started to happen this morning, when im driving the car it seemed to be fine but when im at a stop the rpms stick at around 4k(rpm) and my ecu is chipped with a 3.5k rev limiter(chip made be xencron, so its a good chip) and if i throw the car in nuetral the rpm's will climb and stick at 4k.....now why would that happen??



the cae is a 91 civic ef i have a dohc zc with a t-25 turbo and the ecu is a pr4 chipped(chip made be xencron) ive this set-up for a while(since jan.) and this just started today.

 

How about when ur driving and have it in neutral? Does it fluxuate or is it just steady at 4k. My guess is either Xenocron or your car really wants that thing to be launched at every light

 

if i throw the car in neutral while im driving(not at a stop) the rpm's will go to 4k also....and i dont mind doin a luanch but when im at a stop it aint cool everyone thinks im tryin to rev on em

 

Could be as simple as the throttle adjustment screw backing out from motor vibrations. I have had this before, but never 4000rpm high, more like 1500rpm.

Also could be signs of an IACV going bad.

 

check the throttle cable it might be to tight.

 

vacuum leak??

 

does it do this w/ the clutch pedal pressed or un pressed?

sounds like a launch control limit.

 

I have to agree here too!

 

thorttle cable,i just fixed mine!

 

Id take a vacuum leak the size of your brake boost line to get a 4k idle. Deff. sounds like throttle cable foolery.