Intermittent Idle Surge.

[VerbalKint]

91 Talon NT FWD 5spd.

Had idle surge a while back.

Cleaned TB
Replaced ICS
Replaced BISS

Basically, The Idel surge had gone completly away at this point. Car would run high rpm's while warming up, then settle down into the 750 ish range.

Now, when I start the car, the Idle surge has returned, but only until I drive the car.

If i leave it sit in the driveway warming up, it surges the whole time it sits there.
Once, however, I get in it and drive.. By the time I get to a stoplight / stopsign, whatever, It has decided that it should idle like a good girl.

I've left it sit in the driveway running from 5 minutes to 15, to see if its time related, and it's not.

Just after any amount of driving (at least 5 minutes it seems) the idle surge is gone completely.

Get to work, turn car off... Wait few minutes, start up again, no surge.. Just a perfect, stutter free idle.

Come lunch time, however, she starts surging at startup, until, again, its been driven some.

Just wondering if anyone has a clue as to what's going on here.

I've rechecked the TB, looks good. BISS is still in and adjusted correctly, and ICS tests good.

*shrug*.. Am i just going to have to LIVE with this idle surge?

 

[Turbo Talon DL]

ok, i just signed up on the forum, but been fixin on my car for a hot min. I had an idle surge from hell. I finally ended up pressure testing the intake tract and found multiple vacuum leaks(so subtle u cant LISTEN for them). I got a pressure test kit from machv.com and found my throttle shaft seals were bad. That cured SOME of the problem. Next, are u running water lines to the t-body? There is a post about the fast idle air valve. If u DONT run the water lines to the t-body you WILL idle surge. As soon as i ran the water lines, it started being a good lil' girl Check for vac leaks, do the isc test, and go from there.