Testing Oxygen Sensor Operation - Porsche 928 Workshop Manual

24
Electronic Fuel Injection - LH-Jetronic
928
0
Testing lambda control function.
l.Precondition as for the "sensor
voltage" test.
2.Disconnect oxygen sensor plug.
With length of cable, briefly
connect terminal 1 of
control-unit side of plug
to ground.
The CO reading must increase.
Note:
Do not conduct this test for any
longer than required to detect a
change in the CO reading of the
exhaust tester.
If there is no change in the CO
reading, check connection to LH
control unit and LH control unit
coding (see page 24 - 221),if
necessary, replace control unit.
l
24 - 220 Testing Oxygen Sensor Operation
Printed in Germany