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Idle adjustment

Fuel System

Model: 911, Year:1977, Mileage:8000, Type of use:Street use only
I have about 8000 miles on a rebuilt engine which was purchased 8 years ago from the party I purchaed the car fromI have read your past post on high idle issues when engine warms up. I have adjusted the air mixture screw to where I think I have a good mixture, not too lean or too rich. However the warm engine idle is 1200-1400. Also the engine surges at idle. I read a tech post from pelican parts which implies there is a second adjustment to lower the idle.Below is a paragraph from the post....This brings us to idle speed and how to lower it. If you paid attention, youll know that you can raise or lower you idle speed by changing both the bypass screw setting AND the idle mixture. You have to adjust both, not just one. You can adjust one at a time, and you may find that you will create a lean or rich surge. (That is actually the way you should do it if you are not confident of what you are doing) If you are closing the bypass, and the engine surges, then reduce the fuel. Get the idea? Air and fuel combine to produce energy when ignited. Often a high idle speed is the complaint. So reduce air and fuel to reduce the idle speed. Be wary that you do not have a problem somewhere else which is causing your high idle. Does the bypass adjust the idleJ Where is the bypass adjuster? And does it apply to my 1977 911S 2.7 with k jetronics CIS?The link to this article is: It is quite lengthy. and far above my knowledge.

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