How to do idle adjustment '79 911

[PaleoMan]

Searched but couldn't find much...

My fuel injected '79 911SC Targa has been sitting for years in the garage. I finally got it running recently. It cranks right up and runs pretty smoothly, and now the awful smoking is subsiding.

It runs too fast that, up to 2200 when I first crank it, and never goes below about 1800 when warm.

Before I get in there and mess things up, was hoping to get the proper procedure for adjusting idle. Is it simply turning a screw, and if so, which screw?

thanks!

[boyt911sc]

Do you have a Bentley shop manual for SC's? On page 240-6 is a picture of the throttle body with the idle by-pass screw shown.

Tony

[PaleoMan]

Originally Posted by boyt911sc

Do you have a Bentley shop manual for SC's? On page 240-6 is a picture of the throttle body with the idle by-pass screw shown.

Tony

No I don't, but I will in 4-14 days, just ordered it from Amazon, about $90. Funny, used ones were from $115 up!

Thanks Tony.

[Paulporsche]

It's the big flat screw head just below the red dot. CCW to raise; CW to lower rpms.

Try this and let us know what happens. It may be all you need, but it's also possible there are other factors at play, incl vac leaks, the AAR, decel valve and others, so if turning that screw doesn't solve it, you may need to look at other things.