Idle/Co Adjustment; Checking Idle Speed And Co - Without Catalytic Convertor - Porsche 944 Workshop Manual

24
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.
24 - 106
Air Flow Controlled Fuel Injection
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
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
Idle speed 840 +- 40 rpm
Checking idle speed and CO- with catalytic converte
according
to manufacturer's specifications.
944
86/512
Printed in Germany - XIX, 1989