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Subject:91 Carat - Auto Tranny - 2.1L WBX - RPM Hunting
From:John Rodgers
Date:Thu, 21 Oct 2010 14:49:34 -0500

Howdy Volks,  the saga continues.

To review - the engine idles at 800-1000, above 1000 rpm up to 1500 rpm
and occasionally it would go to 2000. It hunts up and down.

Today, I disconnected the O2 sensor, started the engine. On a cold
start, engine started rough, but did run, but it would hunt wildly up
and down to 2000 rpm. Fancy foot work required to keep it under control.

After it warmed up, I shut it down, disconnected the Idle Stabilizer
Valve. And started it again. Ran smooth as silk from 800 to 2800. RPM
stayed where-ever I had the throttle set with the pedal.

Conclusion: ISV is bad. or or the ISC box in front of the right tail
light is bad.

O2 Sensor may be good. Will hook it back up and try it.

Any opinions anyone?

Thanks,

John

--
John Rodgers
Clayartist and Moldmaker
88'GL VW Bus Driver
Chelsea, AL
Http://www.moldhaus.com