Hi guys

I took my truck to a dealer to have the carby rebuilt (1990 22R).
It took some extra days for them to get the cold (fast) idle set correctly.

I'm taking it back to the dealer as the cold idle is still not correct.
When you start the engine it fast idles at 2000RPM but it hops/bounces between 2000-2200 RPM until it warms up and drops down.
It's very weird, and embarassing too as it sounds like I'm revving my truck when stuck in traffic!

Has anyone got any theories on the problem?
At least then I know if I should be expecting them to re-build it all over again...

cheers

 

My first thought would be vacuum lines. Check to make sure they're all hooked up properly.