Dan, you were right on the money. I also hate ''parts replacers'' but I was to the point of throwing the car in the river. My super-qualified-super-equiped-computer-aided-knowledgeble-expensive Mercedes dealer (where 3 different mechanics looked at the car)spent 8 hours of diagnostic time (without replacing a single part) trying to isolate the problem He ran all the tests on the book (some twice) without finding the cause of the problem. 8 hours of testing (@$90.00 an hour) to tell me ''That's the way those cars were designed''
My independant mechanic also ran the tests, hoping to find one that the dealer misses. All tests demonstrated ''no problem''
Contrary to the Benz dealer, my mechanic did not throw the towel. He kept at it. That's when he started to replace parts in hope of.......
The real problem never showed in any tests. It was most certainly one of those intermitent problem, one of those almost impossible to find except by luck.
I get your point and I fully agree. Parts should be replaced when tested/proven to be defective.
It was one of those cases where it takes what it takes to take the problem away. I'm a little poorer now but much happier with the Benz.
JackD