[Taffy25]

Jumped the terminals to see if i have any codes due to the van running a bit rich and getting a slight miss when up to temp, i had the doghouse off when i did it and i could hear the iac constantly clicking is this normal?

 

[Taffy25]

Just a quick update on this, this thing is clicking like hell now with the van running, thought i had a loose rocker or something for a second, is it suppose to constantly click like twice per second. starting to really not like tbi and all the emission crap that comes with lol.

 

[astro355]

Once the van is up to temperature, the IAC does constantly move. I can't remember ever hearing one move though.

 

[Taffy25]

Yeah this one clicks from cold. it even clicks when ya jump the aldl cable (not one click either, the same constant click as when its running) sounds louder than the pcv.

Also sounds like the motor is surging up and down a couple hundred rpm every couple of seconds, not sure if its related.

Cheers for the reply.

 

[astro355]

The IAC is used to help maintain a correct air/fuel ratio. As the IAC opens, it allows more air into the intake manifold. Now if the IAC is malfunctioning and opening when its not supposed to, more air would be let in than the ECM is aware of and to correct it, the ECM would lengthen the injector pulse adding more fuel to the mixture. That would cause the idle to increase causing a surging affect.

Unplug the IAC and see how the van runs.