My 1999 E300 has no vacuum at the wastegate transducer. When I clear the error code P0243 the car will run without errors until I step on the accelerator. I ran a separate vacuum line over from the other sided of the engine and now I get turbo boost with no errors until I give it full power and blast off down the road. The CEL comes on as soon as my foot comes off the pedal.

I did have a EGR error also but I found the problem there. A mouse built a nest by the brake booster and chewed though the vacuum line supplying that circuit. I no longer get that error. It just seems odd to me that these two problems happened in the same two week time period.

Owning one of these cars is like having an Italian mistress...nice to have but you just know it's going to get expensive eventually.