Ok so heres the problem i have a '95 civic hatch vx with a swapped (not by me) D16z6 ....It has had irratic idle and high idleing problems since I bought it and now since everythign else is pretty much done im starting to take care of it. First off I have traced this problem to the IAC valve? its the thing riding on the back of the intake manifold...
Anyways I have tried replacing it with one i knew worked from my buddies spare engine and it did not work kept doing the same thing only time it idles correctly at around 1.5k =1.6k is when that thing is unplugged ive checked the plug and it reads out the battery voltage....12 v give or take when the key is on and i know the one i just put in there works since he just had the engine i took this thing off of in his car that ran fine.....So I am at a loss right now of what it could be if anyone could help i would be extremely greatful thank you
john

 

i would try to replace or check your TPS sensor, its that black sensor on the back side of your throttle body.if you have a spare motor, just swap out the whole, throttle body.

Also you said it had a z6 swap. Does it have the z6 head and block or just the head??

 

it is the whole swap.......and ive already tried two throttle bodies and i know one worked got it off the same engine as the other Iac valve

 

Check the voltage on your TPS. Should be .5closed and ~4.5 open IIRC

also, is it possible that you bubbles in the coolant system?

are you absolutely positive you're running a z6 intake manifold?

 

not sure about the intake manifold ...how can i tell?? also i know its not the right wire harness i think its the dx wire harness since there is no plug for vtec might that be it and how can i tell if the computer is correct???

 

bump???need this answered asap since i would like to get it on the road soon my volvo turbo no get good milage w/gas

 

find the tag on the ecu and post the code, its on the outside so its pretty easy to find.

Knowing that the wiring harness is not correctly hooked up makes me think that it could be any number of things.

Did you test the TPS?

 

yes i did and i actually without checking the numbers on the computers since i know the one i just put in there was from a 1.6 z6 it idled kinda right again its still hesitant on keeping the same idle but i think once i change over to the correct wire harness it might work?? since once i hooked up the right computer it did shoot a check engine light but it did not rev high like it used to.....anyway to check what it means the check engine i know on a volvo there is a built in led checker???.....

 

anyone i also checked the coolant stuff and did the bleed i guess you could call it to get the air bubbles out no change....would switching the harness really do what im thinking its going to do??