P0170, P0171, P0172
Read the instructions below then start the fault diagnostic procedure.
Symptom: CHECK ENGINE lamp on. Inferior driveability, unsteady idling speed. Possibly other diagnostic trouble codes (e.g. low fuel level, pressure sensor, closed loop, misfiring).
P0170, P0171, P0172 |
Long Term Fuel Trim. All embracing DTC for adaptation function.
Long Term Fuel Trim. Max Value, Air/Fuel too Lean.
Long Term Fuel Trim. Min Value, Air/Fuel too Rich.
Fault symptoms
CHECK ENGINE lamp on. Inferior driveability, unsteady idling speed. Possibly other diagnostic trouble codes (e.g. low fuel level, pressure sensor, closed loop, misfiring).Note | ||
If DTC P0172 has been generated, see also |
Conditions
Ignition switch in ON position.P0171: Adaptation >100 %
P0172: Adaptation <-100 %
Diagnostic help
If the adaptation fault has been caused by low fuel level, P1416 will also be generated.Adaptation can be read with the diagnostic tool.
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Select: "
Data Display / Output Control (New)".
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Select: "
Multiplicative Adaptation".
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Current adaptation ±100 % is shown.
Checking the wiring harness. Intermittent faults may occur in connection with short circuits and open circuits. Jiggle the wiring harness at several points and in several directions to locate any problems in the wiring, including intermediate connectors. Observe the multimeter, scan tool or test lamp during the check.