Hi folks,

just to let you know: the problem of the ever occuring code P4501 has been resolved! Remember I wrote some time ago that the engine was OK from a mechanical point of view and also from an electronic point of view. After determining the circumstances that caused the fault code P4501, we decided to adjust the EGR value via the service part in the tester by a certain percentage. Back from a long trip to and in the mountains we can conclude: the P4501 code did not occure for once during several thousands of km's. Case closed!