88 3.2 surges at idle

[Greg930]

when it warms up when I come to a stop, the engine won't idle smooth, it surges like aI have a racing cam and the idle is adjusted low. The idle is at 1000rpm, but goes up about 150 rpm then back down, and keeps on doing it. Any help. Thanks

[don911]

search for idle control valve. This will get you past threads on 3.2 idle surge issues.

[ZOA NOM]

Begin with known good CO measurement with gas analyzer, or you will be in for a long process.

[Greg930]

Thanks Don and Zoanas, I also have a 930 Turbo but the fuel system in the 3.2 I am not familiar with, just bought it, but will check both suggestions. Thanks again

[jbrand540]

Mine did this at idle in combination with when I would put the clutch in pulling up to a light the motr would drop to about 300 and then quickly recover to 1000 and then would start the oscillating. Mine ended up being a wire coming off the ECM which was disconnected. From schematics I believe it was a wire for the engine speed sensor. After connected everything was smooth as silk. May want to check that your speed sensor is functioning properly.

[Greg930]

the idle control valve seems brand new, so ggoing to check wires as jb suggested then to take it to have air fuel checked. thanks

[aj88cab]

Also check your vacuum lines. There are a couple that connect on the back side of the throttle body and also at the fuel pressure regulator and damper (located at the back right and left of fuel lines).

Good Luck
Andrew

[john walker's workshop]

the ICV may be trying to correct your too high idle. lower it to 880 and see if it's better.

[Zef]

There it is...
Carrera 3.2 idle fluctuation

[scottb]

Start by getting your mixture checked. If the mixture is within specs, then start looking at replacing parts. I had a similar problem and replaced the O2 sensor, idle control valve and head temp sensor. Nothing helped, until I had the mixture set. Problem solved.