Emer925

Hi I have a civic 97 ex auto. I recently replaced my iacv and noticed it was really dirty . When I put on the new one After turning on the car it was fine than after it warmed up the idle started going up and down from 1000-2000 rpm . My car did not do this with my old iacv . I also used the same old gasket with the new iacv. Do I have a vacumn leak or is it a faulty iacv ?? Thanks .

TomCat39

You didn't specify but I'm assuming stock 97 EX so D16Y8 motor automatic.

Not using a new gasket is quite likely an issue. You can verify a vacuum leak by spraying around the area with throttle body cleaner. If the rpm changes in tune with spraying it is typically an indication of a vacuum leak. To confirm you can raise the rpm via the throttle cable bracket on the throttle body and spray around the area in question (IACV/EACV) with the throttle body cleaner and if the RPM changes only during spray and returns when you stop spraying it confirms the vacuum leak.

The other part of your question will require you to Google "factory service manual 96-00 civic".

In the factory service manual it will show you how to test the IACV (EACV) to see if it's faulty.

Travlash

I would check the vacuum line from the cruise control module on the driver side, the vacuum line goes from the cruise control module to the intake manifold on the back underneath the manifold, make sure it is still plugged in.

Emer925

Ok thanks for the info guys!!

Emer925

Thanks so much the problem was that the cruise control hose was just hanging . Now that I connected it to the manifold my idle is perfect

Travlash

No problem man , glad I could help .

White_crex

This is awesome i am so glad i looked on here before buying a new iacv, this helped me out with my 00 civic ex ended up thecruise control vacuum line was just hanging like said above^^^