idle issue

[turner16]

I have an idle issue. When the truck is well warmed up she revs to high. My idle set screw is all the way out. Could this be a kickdown problem? It is a new cable and I pushed the pedal all the way to the floor to set it? There is slack in the cable when not pushed to the floor

Any help is much appreciated

[MagmaJct]

Possible Causes:

1) Timing set too high.
2) Something is preventing the throttle from returning completely. Poorly set throttle cable?
3) Vacuum leaks, likely the mixture is set too rich also, to compensate for said leaks.

[Wrenchbender Ret]

If you have a Q-jet carb, this is usually a sign of worn thottle shaft. Sometimes a spring connected to the top, cable connection helps. But you will need to get the throttle body rebushed. Also make sure your choke is going off completely & the fast idle cam is not sticking.

[turner16]

Originally Posted by Wrenchbender Ret

If you have a Q-jet carb, this is usually a sign of worn thottle shaft. Sometimes a spring connected to the top, cable connection helps. But you will need to get the throttle body rebushed. Also make sure your choke is going off completely & the fast idle cam is not sticking.

the carb was professionally rebuilt and set up, would they have caught this?
it is a QJet Rochester

[68gmsee]

Originally Posted by turner16

the carb was professionally rebuilt and set up, would they have caught this?
it is a QJet Rochester

If it was a true carb shop that did it, that should have been one of the things they check. If it's the throttle shaft, you can check it yourself by manually pushing it to see if it slows down.

[screaminchevypickup]

Sounds like a vacuum leak to me!!!
Posted via Mobile Device

[turner16]

I use to have a vacuum leak. I'll see if I can find a tester