i have a 95 civic ex just put a newer d16z6 in it. the car will idle really high (2000-2500) when cold and after a couple seconds the idle will start jumping from 1000-2500 untill the car is warmed up. then occasionally the idle will still jump when im at a light idleing or sittin in the parking lot. any one have any suggestions?

 

check your coolant level

 

do you have any CEL's?

 

lmao, are you serious????????? are you just guessing?

OP: i have this same problem and from what ive personally read many times is that its 99.9% your IACV, i will post a thread on how to clean it n' stuff

ive clean mine before too and it worked for a little and started doing it again, if you clean yours and it does that bouncin idle again, you may have a defected IACV

 

here is the thread btw: https://honda-tech.com/forums/acura-integra-6/%2A%2A%2Ahow-clean%2A%2A%2A-your-iacv-k-idle-air-control-valve-1575913/

 

no hes not kidding. if he has low coolant then air pockets will form and it can cause the IACV or FITV to fluctuate

 

oh ok, never head of that being the problem

 

yeah that took a while for me to figure out. it sounds completely unrelated but it makes sense

 

Here is a link for bleeding the coolant http://www.hondacivicforum.com/forum...ad.php?t=41650 , but if you haven't messed with anything coolant related that is unlikely you problem. Cleaning your iacv and fitv will never hurt. It sounds like your problem likely is fitv which regulates the cold idle, but it is could also be a combination of both since it is jumping like that. Here are links to clean the two of those https://honda-tech.com/forums/showthread.php?t=1575913 and https://honda-tech.com/forums/acura-integra-6/%2A%2A%2A-how-%2A%2A%2A-clean-your-fitv-aka-fast-idle-thermo-valve-1564019/. The latter is the fitv pay careful attention to the third from last picture and caption. Many people overlook the fact that depending on how far you turn the nylon fitting will adjust your cold idle speed. Additionally you should check for a vacuum leak. The easiest way to do that is take your air filter off, cover the throttle body with your hand and the car should die. If it doesn't die within three seconds then you have a vacuum leak.