SC High Idle (warm)

[Combat 911]

So, I've replaced my Auxiliary Air Regulator, Auxiliary Air Valve, and most of my vacuum hoses and my '83 SC is still idling at 1,400-1,500 RPM once it is fully warmed up. Any suggestions???

[pbs911]

I hate to ask, but have you tried the idle adjustment screw? Also is the throttle linkage adjusted properly?

[drwest]

speaking of the idle adjustment screw. One would have to try REAL hard to find a more difficult place to put that adjustment. Why did they have to make that soooo hard to get to? Is there an easy trick to adjust that pup?

derek
79SC

[wckrause]

Are you kidding? It's easy to get to. Are you sure you're adjusting the right thing?

[Vipergrün]

Have you tried unplugging the decel valve? If not, try unplugging the vacuum hose from the round unit just below the fuel distributor are on the right side of the motor.

cheers
-Brad
80SC

[Combat 911]

Thanks! I didn't think of it being the idle adjustment screw because it idles nicely when "luke-warm", then speeds up as it warms to normal operating temperature. I'll break into the Haynes manual to verify the idle adjustment.

I will also try disconnecting the vacuum line from the deceleration valve. Couldn't hurt to try it.

I sure appreciate the help!

[Targa77]

Aren't there two hoses that go to the valve? I have heard that you should disconnect the middle one and plug it. Someone correct me if I'm wrong.

[jrdavid68]

Originally posted by Combat 911
So, I've replaced my Auxiliary Air Regulator, Auxiliary Air Valve, and most of my vacuum hoses and my '83 SC is still idling at 1,400-1,500 RPM once it is fully warmed up. Any suggestions???

Quit beating your self up over this one. Just upgrade to a Carrera with the extra .2L and be done with it...

JrDavid68
1986 Carrera

[john walker's workshop]

left hand thumb and forefinger. reach in there and turn the idle speed screw clockwise down to 950 or so. do it when the idle is highest/engine hot.

[Targa77]

John, whenever I have tried this (engine hot), as soon a s I let the engine cool down and go to re-crank it, it will not even idle. Any suggestions?

[Combat 911]

Thanks all! The "idle adjustment screw" seems to have cured my ills. I still can't find a description of it in my Hayne's manual. Does it adjust the angle of the throttle valve? Wish I would have tried that $300 ago... (Would've made a nice step towards that Carrera chain adjuster kit...)

[Targa77]

bump