| Confirmed with the dealer - the cam magnet sensors are leaking on high mileage M271 engines.
Its a $500 part and 6hrs of labour to replace the engine harness.
The typical failures are the O2 sensors as the oil destroys the sending units.
So far this year:
$300 MAF
$250 for both O2 sensors
Now:
$100 cam magnet sensors
$500 engine harness
$250 possibly new O2 sensors since the CEL is back
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