QuestionI own a 2003 VW Passat V6. Recently, the engine light has been on. The OBD test at the dealer showed a code of P0348, and the dealer went ahead to replace both cam adjusters and cam sensors.
However, the engine light is still on, and a subsequent OBD test is still showing the same code. What else could be triggering this code? Many thanks for your input.
AnswerEve,
A couple of things I have heard:
- If you've had a tune up and the timing is set improperly. Especially if the timing belt is replaced and is off by a tooth or more.
- Believe it or not, a cheap oil filter replacement. Somehow this can affect the intake to exhaust timing relationship, perhaps because of improper back pressure on the oil pump, which is driven by the cam. Whatever the reason it's an easy fix, use only VW filters designed for your vehicle.
Otherwise, it must still be a problem with one of the cam position sensors. Either there the replacements are inferior, installed incorrectly, there is a bad connection(dirty/greasy electrical connection) or they may have gotten moisture in them at some point. This is all assuming the original OBD error was cleared and this is a new instance. There is a possibility that the signal back to the computer is "open" at some point not actually at the sensor connection, say because of some loose/corroded multi-pin connector within the wiring harness which this signal passes, but where this might be is tough to say.
- Rick
