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P1372

P1372

Diagnosis information - DME V8 DFI

Valve lift control, bank 1

NOTE: Diagnosis detects via the lambda controllers that all valves of bank 1 have either not switched to the other lift or have not switched quickly enough in valve lift switchover.

Diagnostic conditions

NOTE for Turbo vehicles If no fault is detected in the short test, it is necessary to additionally carry out a test drive (see below).
- Perform a short test
or
- Engine oil temperature -11 °C ... 111 °C (12 °F ... 232 °F)
- Small lift:
- Engine speed between 1,200 rpm and 3,000 rpm
- Mass air flow between 150 mg/stk and 400 mg/stk
- Large lift:
- Engine speed between 1,500 rpm and 5,000 rpm
- Mass air flow > 550 mg/stk ... 325 mg/stk

Possible fault causes
- Insufficient oil supply for faulty bank 1
(e.g., due to faulty scavenging restrictor in the cylinder head, dirt in the oil circuit, ...)
- Greatly differing exhaust backpressure values between the banks
(e.g., due to constricted or blocked opening of an exhaust branch)
- Loose contact or corrosion on connectors or lines
- Solenoid hydraulic valve for valve lift control on bank 1 faulty
- Incorrectly adjusted timing of the intake or exhaust camshaft of a bank
- An oxygen sensor is aged or faulty