Bad= the parts were crap from day one. I've replaced enough of 'em to fill a small house.

That still does not give an accurate description as to what their failure mode is.

How parts fail matters just as much as that they have failed and need replacing.

What matters to the majority of DIYer's, as well as the clients who patronize my dealership, is that the car is fixed. Failure analysis is best left to the manufacturer/engineers. That's what they get paid for.


Concerning your original statement, "We need to define " bad " .. Have the magnets lost magnetism or are they swelling.......", I don't know how any technician would be able to determine this. I've had quite a bit of MB technical training over the course of my career, but I've never been trained how to determine "magnetism" performance!


FWIW, the issue with the cam solenoids (as I've been told by MBUSA), has to do with manufacturing tolerances/hardening of the magnetically actuated plungers inside the solenoids. Movement of the plunger either directs or restricts oil pressure flow within the cam timing device. Over time the plunger surface can become scored, eventually resulting in the plunger becoming sluggish, or completely stuck. When this happens the cam position sensors report the data to the engine management system (ME 9.7). Once ME 9.7 determines one or more camshafts out-of-position via mapping software/logic chain, a fault code is set.

All this tech-talk might be interesting to kick around on the Forum, but IMHO it doesn't really help fix the car.

I agree that most people who patronize a dealership for repairs only care that the car is fixed. But DIY'ers like myself do want to know why and how parts fail. The explanation was appreciated, but not the lecture.

__________________
Resistance is Futile.

DIY people _need_ some concept of how a part works and how it failed.

As for clients, those with a engineering bent would want to know something about the repair. The stock broker probably would not.

It sounds like you are randomly changing the magnets not knowing why then need to be changed. What prompts you to change them? Is there a light on the dash like a 80's Oxygen sensor / Emission mileage counter?

A similar situation would be telling customer a tire is " bad ", then when asked what is wrong, you reply " It's bad and that is all you ( or I ) need to know" . For a tire there is a range of bad, worn tread, bulge, sidewall cut or something as simple as it needs air because it hasn't been checked in a while.


Now this info brings new terminology to the mix. When someone says " Magnet" that is generally considered to be a ferrous materiel with a north and south pole. Like a fidge magnet.

Now, you are speaking of "SOLENOID ", as in ELECTRO Magnet . , that is an entirely different entity. Remember, in my first post I said I didn't know what the " magnets " looked like and played it like the _Crankshaft_ position sensor that looks at magnets on the flywheel.

The description you gave is what I was looking for , wasn't that hard was it?