My rpm started jumping up and down recently, espically when the car starts at cold. Is this due to my iacv or is his because of my cel from my test pipe. The rpm/idle do jump every here and there at stop lights. Inputs would help, thanks!

 

In for results, my Evo has been doing the same thing since i installed my ams front mount, I was thinking it could be a vaccum leak, just haven't checked my couplers/lines yet. Have you checked for vaccum leaks?

 

has anything changed? did it just happen out of no where?
did u disconnect the battery at some point and then it started doing it?
lack of info.

diagnosing on the web with ur info is like shooting in the dark at something someone said is over there.

 

+1 it could be a number of different things. More information about the cars history is needed.

 

I got a couple things done. First week I had the intake swapped out and changed my sparkplugs. Drove the car for about a week and it ran fine. A week after I switched out my whole turbo back exhaust, this time instead of a high flow cat I used a Megan testpipe. Couple days later a cel came on. The cel is from the no cat, however would this cause my idle to be jumpy and cause the car to stall at a dead stop sometimes? This also had happened to me before a couple months ago. I might have thought it might have been the idle air control vavle, but just when I was about to get it checked out the problem went away.

 

I sometimes get the jumpy rpm waiting at the light. I lightly press gas till 1000 and it goes away

 

my car stalls at time... could this be caused by my bov also? i read somewhere the bov might be able to cause jumpy idle/stall. Can someone chime in and correct me on this. thanks

 

i have a tial 50mm bov and my idle dips below what its set at when i come to a stop and sometimes stalls. buschur 4" fmi too. no idea what it could be..

 

Id say check for any vacuum leaks and make sure your couplers are all snug as it could be a small leak in the system. The stalling could definitely be attributed to this.

I also had this issue when my alternator was on its way out... although I find that unlikely to be your problem.

 

Ok I'll check on it in a couple days when I have the time to take off my bumper and do a thorough check. Thanks for the advice. Would a bad iacv cause this also? I'm not sure why but I keep having doubt on it for some reason.

 

If you hhave a tial bov and the car isnt tuned... thats the issue. You need either a tune or to recirculate the bov. If it is recirculated, yes a iacv could cause the problem.

 

Good luck man, I just replaced my IAC today and havent been able to locate it yet. Im tuned also with a Tial QR. There was another thread on here about it. I dont know what happened to the other guy in it.

 

not sure if you meant your looking for the IAC location. its on the throttle body under the intercooler coupler. i would remove the strut bar to make working in that area easier.

luis

 

^No sorry I just replaced mine and the issue is still continuing.