Idle runaway!

[Big_P]

85 'baron 2.2 tbi auto. Almost ready for PAINT! Anyway, I deleted the egr when the head was off. it had an intermittent high idle problem I was hoping was a bad IAC but maybe not. Anyway, it'll idle fine most of the time, but of you let it sit running in park sometimes it'll start to creep up and up, somewhere around 3300 rpm. No codes and I tapped the IAC (or whatever they called it in 85- it's a weird looking thing) with a hammer in case it was sticky but it seems like the computer wants it to idle up. Any ideas? No codes.

[shadow88]

Do you have a scan tool to see the idle counts?

[Big_P]

My Genisys says it's running 4400RPM when the engine is off, and every sensor is putting out 2.51v. Obviously some communication error there. Did that with my last TM too. I wish I could talk to it :\

[R/T]

Try taking the AIS out and cleaning it with carb cleaner, then WD40. Maybe it's sticky.

Or just unplug it. :D

[turbovanman²]

Try a different year when scanning it.

I would unplug the SDS sensor and try that.

After it high idles, shut it off, remove the IAC and see where the pintle sits, that will give you an idea of what the computer is doing.