Need help guys.. I swap in a 2000 LS motor into my 94 civic si Hatchback. Everything went well until I started up the engine. It idle about 2100 when the motor is cold and it would jump up and down from 1400 to 2100 rpm when motor warms up.
I've clean the iacv w/ brake cleaner and also used a different iavc(used) and still have the same problem. I've check my vavcuum hoses and radiator hoses but no leak. Bleed the radiator and still have the same problem. I also check my plugs and the right plug is plug into the idle control unit. No check engine light on(yes, it works). But when I plug the iacv hole in the throttle body it runs and idle perfect. Anybody knows whats going on here? Thanks guys.. Hope you all can help me out here.

 

I'm running my civic si harness with the P75 obd1 (94-95) integra ecu. I've also check the vacuum line and its correct. Hope that you guys can help me out here, thanks.

 

Maybe your throttle cable is too tight, ive seen it happen.

 

My cable is not install on the throttle yet, I've also check my FITV and its clean. Did my timing and its good, please help me out here, Thanks guys..

 

Still having the idle problem and need help...

 

I had the same problem.. It was my Throttle Body gasket that was jacked up.. Heres an Idea.. Get some Carb Cleaner and Spray around your intake manifold and if the Idle goes down when you spray in certain areas.. Theres your LEAK!! Try it out and let me know what happens I can almost gurantee its your Gaskets Leaking.

 

check for leaks,

IACV?

 

Thanks a lot.. That was it, I did what you suggested and found the problem. Bought my throttle gasket at Acura dealership wich cost $6 and replace the old one. My idle problem is gone and the idle is sitting at 800rpm. Thanks again!!

 

make sure ur throttle cable is placed the right whey because theres 2 holes that u can choose from when it comes to mount of the bracket for the throttle cable. if its not the throttle cable then it could also be your O2 sincers. i think? u should check them.