Your situation sounds very systematic of a problem related to the wiring harness. I'd even venture to guess that the head gasket was replaced some time ago. The head gasket job is very traumatic to the brittle wiring harness.

You won't be wasting your money to replace the wiring harness. In fact, some mechanics refuse to work on a problem such as yours unless the wiring is replaced. Go ahead and replace the wiring, then continue on the injector problem. It's a good bet that the injector problem will go away with new wiring.

I share your sentiment with MB vehicles. Not a year goes by where I don't have to repair or replace some major electrical function on the car... and I only put 5K on this car every year! Once I've finished my term with this vehicle, I'll be looking for something else. I've never had such problems with any American make.

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95 E320 Cabriolet, 169K