High Idle At Start-up. Why??

[jeff*k]

i have an 86 gn, bone stock with 86k miles. the car revs high 3-3.5k then slowly comes down to normal. any ideas???

 

[salvageV6]

TPS and/or IACV mis-adjusted. What scantool are you using?

 

[jeff*k]

don't have one yet

 

[WarpSpeed]

Too much minimum air setting.
The screw on the side of the throttle body.

 

[salvageV6]

Don't touch it without a Scantool.

Borrow one to set it properly.

 

[John Larkin]

Hmmm, mine jumps up to about 2200, then settles down within 30 seconds. I thought I remembered TurboJim saying that this was some sort of startup enrichment in the chip usually. Maybe it can be adjusted out, I dunno.

 

[jeff*k]

i reset iac, no luck. i will check tps. anyone have the correct voltage setting for idle and wot??

thanks

 

[WarpSpeed]

.42-.45 idle engine on, 4.50 WOT is nice, more impotant, make sure throttle is all the way open when floored.

Try this, ground IAC( paperclip between top right 2 connectors on adld connector under dash.) Turn key on, after 10-15 secs, unplug IAC, and turn key off, remove paperclip. Start engine, adjust idle with mini. air screw to 650rpm or so. Adjust TPS too. Turn car off. Plug in IAC and start car. Recheck TPS.

It's ballpark but best you can do without a scan tool.

 

[KendallF]

Originally posted by jeff*k
i have an 86 gn, bone stock with 86k miles. the car revs high 3-3.5k then slowly comes down to normal. any ideas???

Stock chip or a Red's chip, by any chance? These have a very high cold start idle, then taper down. Try a Thrasher or other chip and I'll bet it goes away.