[tms7447]

My 1991 Honda accord runs perfect but idles up and down all the time when is in the parked position.

[TxGreaseMonkey]

Cleaning Idle Air Control Valve (IACV)

In order for Hondas, and many other modern-day cars, to idle properly, the IACV needs to be cleaned. Here's how to perform this simple task:

1. Remove IACV electrical connector.

2. Remove both bolts (12 mm) securing IACV to plenum.

3. Remove both IACV hoses.

4. Clean IACV and hoses with a spray can of brake cleaner--be sure to wear safety goggles.

5. Install new O-ring, if necessary.

6. Remove air intake from throttle body. Ensure upper and lower throttle body ports are clean. Dirt tends to build-up around top port.

While you are at it, clean the throttle plate, throttle body, and air box; afterwards, install a new air filter.