Porsche 944 Automobile User Manual


 
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Fuel System - Electronic Control 944 S/944 S2
Adjusting value: 0.5 - 1.5 % CO
at 840 +- 40 rpm and ignition timing of
10° +- 3° before TDC.
Adapt the system after adjusting the CO level.
An adapter plug (911.612.422.8) must be con-
nected on the oxygen sensor connecting lead
of cars without a catalytic converter, in order
to avoid diffusion (see wiring diagram).
c) Idle speed CO of cars with catalytic
converter
In addition to adaptation of the idle speed
there is also adaptation of the idle speed CO
level in these cars, so that it is only necessary
to check the actual state in such cars.
Requirements:
-
Engine at operating temperature.
- Engine and ignition in perfect running
condition.
- All electric consumers switched off.
- CO tester at operating temperature,
calibrated and adjusted correctly.
-
Oxygen sensor plug connected.
Test value: 0.4 - 1.2 % CO
at 840 +- 40 rpm and ignition timing of
10° +- 3° before TOC.
Afterwards the engine must be run at least
10 minutes after disconnection of the
control unit plug or disconnection of the
battery, before it will be possible to recheck
these values. In addition, the system must
be adapted.
D 24/28 - 30
DME - Diagnosing/Troubleshooting
Printed In Germany - XXII, 1990