93 dies after 20 seconds of idle

[Terry_Jim]

LAst week, exp was running rough,on the way home from work,
I found that the plug on vacuum port at rear of plenum had fallen off, I re covered it, and it runs OK.
NO Check Engine Light.

But, when it starts, the idle runs high for about 20 seconds, then kicks down low and goes lower till it stalls.

Restarts, drives ok currently, once it warms up it is fine, but problem repeats on restart.

I cleaned the throttle body, butterfly valve,
and also the MAF sensor(with appropriate cleaner).

No change. any other ideas?
Thanks!

 

[Turdle]

Sounds like the IAC valve is sticking. You might try cleaning it.

Inside will be a small rod with a sliding valve. make sure the rod and valve seal are cleaned well. It may help to use a small needle nose pliers to move the plunger back and forth so you understand how it is supposed to work.

 

[Terry_Jim]

Thanks, Turdle! I found pics on IAC cleaning here -> http://www.explorerforum.com/forums/showthread.php?t=84220

I'll do that next.