911 SC Cabriolet F6-2994cc 3.0L SOHC (1983)
Air/Fuel Mixture: Adjustments
ADJUSTING IDLE - 911 SC
Adjusting
Note: Make sure oil tank cap and seal fit properly before adjusting idle. Leaks through oil tank cap would cause incorrect readings.
Adjusting requirement:
Engine in perfect working condition and ignition timing set correctly.
1. Connect exhaust gas tap on test connection of catalytic converter.
2. Run engine to operating temperature (oil temperature about 90 °C/194 °F; oil temperature gauge needle at upper end of field outlined in white).
3. Connect CO tester according to instructions supplied with equipment.
4. Disconnect oxygen sensor plug in engine compartment on left side.
5. Turn control screw or bypass screw on throttle housing until specified engine speed is reached.
Specification: 900 ± 50 rpm
6. Check CO level. If CO level does not correspond with specified value, remove mixture control unit and remove threaded part of shear-off screw in
access bore for mixture control screw.
