Is it normal for the IAC (2.8l) to make a clicking sound with: the key on (engine not running) and the diagnostic terminals jumped.

I was doing some other checks and noticed this.

Yes that is normal, it sets the IAC all the way closed, and keeps clicking to close it more, because the ECM doesn't have any way to know what position it's in, so when crossing l cruising at speed or with those pins jumped, it extends all the way to reach a known zero position, which it then can idle from.

See https://web.archive.org/web...erocave/idlestop.htm Bottom section.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

don't hook up the diagnostic terminals with the IAC outside of the throttle body... thats the only thing preventing the pintle and spring from flying out, never to be found again. Don't ask me how I know…

quote Originally posted by gregr75: Don't ask me how I know…

Happens to the best of us. lol