Porsche 944 User Manual
Page 122
24
Air Flow Controlled Fuel Injection
944
Checking idle speed and CO
without catalytic converter
Model 87 onward
Engine type M 44.40/41 (3.0 l)
Note
It is no longer possible to adjust the idle
speed. The throttle valve connector
adjustment therefore no longer applies.
Idle/CO adjustment
Adjustment preconditions
Engine in perfect mechanical conditions.
Consumers must be switched off during
adjustment work. Carry out adjustment as
quickly as possible to ensure that the intake
paths do not heat up thus falsifying the CO
value. Ambient temperature 15 - 35° C.
1. Warm engine up to operating
temperature.
(70 - 90°C oii temperature). Use oil
tempe-
rature tester, Special Tools 9122 and
9122/2.
2. Check CO value. If the CO value is not
within the prescribed tolerances. correct
the setting at the air-flow sensor. Remove
the sealing plug in the access bore to
the CO adjusting screw.
Engine type M 44.40
Standard screwdriver for 3 mm Allen screw.
Engine type M 44.41 (3.0 l)
Standard angled screwdriver for 5 mm
Allen screw.
Illustration shows engine type M 44.40
86/512
CO setting: 0.5...1.5 %
Turn to the right - richer mixture
Turn to the left - leaner mixture
Checking idle speed.
1. Connect separate speedometer
according
to manufacturer's specifications.
Idle speed 840 +- 40 rpm
24 - 106
Checking idle speed and CO- with catalytic converte
Printed in Germany - XIX, 1989