Porsche 944 User Manual

Page 121

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944

Air Flow Controlled Fuel Injection

24

Checking idle speed and CO-

with catalytic converter

Model 87 onward

Engine type M 44.40/41 (3.0 l)

Note

It is no longer possible to adjust idle speed

or

CO on vehicles with catalytic converters. The

Lambda probe remains connected while

chekking idle speed and CO.

Checking preconditions

Engine in perfect mechanical condition. Con-

sumers must be switched off during checks.

Carry out checks 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. Fit standard exhaust adapter to the test

connector of the catalytic converter.

Engine type M 44.40

86/463

Engine type M 44.41 (3.0 l)

173-24

2. Warm engine up to operating

temperature.

(70 - 90° C oil temperature.) Use the oil-

temperature tester, Special TooIs 9122

and 9122/2.

85/114

3. Do not separate the connection for the

Lambda probe. Connect CO tester and

separate speedometer according to the

manufacturer's specifications.

CO reference value 0.4...1.2%

Idle speed 840 +- 40 rpm

Checking idle speed and CO- with catalytic converter

Printed in Germany - XIX, 1989

24 - 105

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