Just bought a 97 3.4 2wd Tacoma and truck runs great with one exception. It idles high... constantly. This fast idle will continue whether the temp gauge reads cold or fully warm.

I suspect the IAC valve and will get to testing it this weekend. Just looking for suggestions from others. I've checked the vacuum hoses and all seem good. I've also checked and adjusted the throttle cable and also lubed it to insure no binding is taking place. Also shot some cleaner in the throttle body hoping it was a gunked up mechanism, but it, too, turns freely.

When I disconnect the connector to the IAC valve, the idle goes down, but not quite to the level I would think is "normal". (sorry, no tach in the truck... very basic model)

Any help would be appreciated.

 

is your A/c on

 

Idles fast with a/c on and off.

 

any check engine lights? did u check for vacuum leaks around the intake manifold? upper and lower.

 

CEL only after I had disconnected the IAC connector to drop the idle. After it was reconnected, I cleared it with my OBD2 scanning tool. Hasn't come back on.

I checked the hoses I could find... where are the lower hoses you speak of?

 

see if u can use the scantool to check the data list. see what your idle rpm is when its fully warmed up. maybe it just sounds like its idling high if your clutch fan is going bad.

im not talking about lower hoses. the 3.4 intake manifold can separate. theres an upper and lower gasket. spray throttle body cleaner around the gasket when its running. if the idle jumps, you kno where the leak is. be sure to have some compressed air and an air chuck to blow out the flames if the throttle cleaner catches fire.

 

Thanks. Quite sure the idle is running high and not just sounding high. I do have an old clip on tach I need to dig out from the back of the garage somewhere.

I'll check for leaks this weekend with fire extinguishers handy.

Mahalo