Otto Mechanic

More possibly relevant diagnostic info.

Starting the car cold runs up to about 2000, falls back to almost 0, catches itself and runs back to 2100. It does this a total of three times (twice more after the cold start), then stabilizes at 2100.

After warming a bit it drops to 1800.

Once warm, punching the throttle up to 4-5000 and releasing causes it to drop back to somewhere between 3100 and 2100 and hold there. Hitting it again may cause it to drop from a 3100 idle to 2100, but it doesn't want to go back to 1800.

Putting it in reverse or drive drops it to a standard 750 idle.

Right now I'm thinking I either have a bind in the throttle cable (it feels loose though) or a sticky TPS.

Otto Mechanic

Fixed it. It was the idle screw adjustment on the throttle body, it was locked all the way at maximum right. I broke it loose between the first and second intake runners but didn't really move it. Years ago I must have pushed it all the way to the right stop while compensating for the slow MAF degradation.

I didn't adjust it left more than maybe an eighth of a turn and it settled at a 500 rpm cold idle.

Let's hope I have this much luck in the future?

Thank every last one of you for your help on this. John? Special thanks. Louie? Same to you. Ken, Sean, Fred, Roger! all the others, what can I say? I hope you'll all be here next time. My guess is this adventure is never over...

walishah

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