So, Ken, once I disconnected the O2 sensor, and the ISV, the engine
now runs sweetly through the full range. How is it that the throttle
position switch is involved? If it was the switch, I would think there
would still be problems.with hunting. What am I missing in my
understanding about how the system works?

Thanks,

John

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

On 10/21/2010 4:43 PM, Ken Wilford wrote:
> Check throttle position switch.  I beg of you :'(
>
> Sent from my Samsung Intercept™
>
> John Rodgers<inua@CHARTER.NET>  wrote:
>
>>   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