high rpm at start-up

[Bandit1200]

i have a 96 xlt with the ohv ,,at start up the rpms go up to 2500 for about 3 seconds then back to normal.this happens when cold and warmed up.i did a scan it came back erg flow less than normal.
can anyone help??

 

[Iggy flywheel]

high rpm

check the IAC idle air control too and go over vacuum hose.
see if that helps....

 

[Bandit1200]

where is the IAC,,and how do i check it,
thanks for your help iggy

 

[Bruce L]

Your IAC is a motorized "valve" which regulates air bypassing the throttle plate. It aids during engine warmup and keeps steady idle when the engine is put under a load (ie. A/C Compresser). It's mounted next to the throttle body. Hope this helps.

 

[Iggy flywheel]

IAC

It is located on the plenium that leads into the intake manifold on the driver side and has a electrical connector. Haynes manual shows it but you can check the electrical connector to see if getting juice 10.5 to 12.5 volts. Then check the resistence of the valve itself across terminals 6.0 to 13.0 ohm's then terminals to body 10.000 ohm or greater. Then take the 2 bolts off that hold it to plemium check inside to see if the valve moves back and forth. Clean it. I used carb cleaner. This is temp fix will have to replace it if bad..

 

[Bandit1200]

i cleaned the IAC and it solved the problem,,now i have a new problem there is a howling noise coming from the throttle body.
what is this??????noise

 

[Bandit1200]

Does anyone know how much a new IAC would cost?

 

[Bruce L]

I don't know how much a new one is. The howling noise is probably the air flowing through/past the newly cleaned idle air plumbing.

 

[Bandit1200]

The IAC started to stick again so i bought a new one from autozone 63.99. The howling noise is gone now ..runs great!
thanks for all your help