Porsche 928 Workshop Manual page 71

03
Maintenance, Self-diagnosis 928
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Error code 1122
This error code indicates a fault in the area of
the rotary idle controiler.
Note:
A functional check can be carried out using
the actuator and input signal functional check,
In the event of an error, check the cable har-
ness wtth reference to the circuit diagram.
Error code 1123
This error code indicates that the Lambda con-
trol has detected that the mixture is too rich.
Possible causes for too rich a mixture
System pressure too high
No partial vacuum at the pressure regulator
Injection valve does not close
Blockage in the return line to the fuel tank
Misfiring
Short-circuit to positive, Lambda probe
0.3 - 24
Trouble-shooting
Printed in Germany - XX, 1908
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