No idle when warm

[wards]

I have a stock 92. It starts fine when cold, but when is warms up, it will not idle. I stop at a light, starts to run rough, then the relays under the dash click and then stalls.

Any ideas?

[TheresGabe]

Sounds like you need to adjust your idle. The festiva will naturally idle higher until the engine is warm, and then it calms down once it gets going. Sounds like yours is set low, so it's idling normal when it's cold, and won't idle when it warms up. It's a simple screw on the intake manifold.

[wards]

Thanks!

I will check the setting this evening.

[Pu241]

I suspect the thermal sensor on the intake manifold has failed.
It is the green plug sitting on the passenger side of the engine on the bottom side of the intake manifold.

[wards]

Checked the idle and it is here ranked down all the way. I took off the idle air control bypass valve and cleaned it out.

Now at idle it does not stall, but lopes. It idles and drops, then idles and drops.

Anyone know what the thermal sensor is called so I can try and replace that?

[FestYboy]

if the screw is cranked all the way down, it's too low. the set screw is ment to be adjusted ONLY when the car is up to temp and at idle. any idle when cold is controled by the IAC. after warm up the IAC goes off line.

[wards]

The idle screw is actually a quarter turn from being cranked down all the way. Idles very high, then lopes a bit then back to high.

Know of any Festiva experts in Columbus, Ohio? LOL

[Bert]

A few years ago I developed an irritating 'loping idle' once the car warmed that was solved by adjusting (trial and error method) the dashpot. It is somehow affiliated with the TPS throttle position sensor. As you can see from all the terminology around here with these electronic cars it doesn't hurt to invest in a Haynes manual.

[wards]

Replaced the violent temp sensor. Still surges and idles high. Going to look at the dashpot and tps next