QDear Tom and Ray:

I take my car to the dealer and agree to a $89 diagnostic fee. The dealer calls me and says, "You have a vacuum line that popped off, and the total fee, including diagnostics, will be $153." I say, "Wait. I need to think about it." I arrive at the dealership, find my vehicle and start it up. All seems to be fixed. I go to the service counter to pay my $89 diagnostic fee, and the dealer says fine, but wait here for a while. He proceeds to run out back with a mechanic to disconnect the vacuum line. After all, I am only paying for the diagnostic service. I catch him in the act and make him stop. Who is right? Do I allow him to intentionally break what he already fixed because he was not supposed to fix it? Is it wrong for a mechanic to intentionally break anything?

-- Tom

ARAY: I'm afraid we have to side with the dealership. While $64 is a little steep for reattaching a 64-cent vacuum hose, the dealer is correct in principle.

TOM: Here's the scenario. The mechanic does the diagnostic work and concludes that you have a vacuum leak. He tells the service manager, who presumably plans to call you to get your approval.

RAY: But while the mechanic's got the car in his bay, and he's got the hood open, and he's got the air filter off and wires pulled out of the way, he decides to go ahead and fix it. Not only is it easier to do it when everything is fresh in his mind, but by fixing it, he can confirm that he's correctly diagnosed it. And once he's confirmed that it's fixed, he's not going to "unfix it" until you call back and then have to "fix it" again. So he leaves it "fixed."

TOM: It's true, he fixed it then for his own convenience and took a risk. He didn't want to pull your car out and then have to pull it back in and start over later. That was his decision, and you have the right not to pay him for the repair.

RAY: But if you decide not to pay, he has the right not to give you his work.

TOM: Let's say you needed a new headlight. If they plugged one in to make sure it fixed the problem, and then you decided not to pay for the bulb, they'd certainly have the right to remove the bulb and keep it, wouldn't they? Well, ethically speaking, the same is true for a service.

RAY: It was awkward, but what he did was certainly within his rights. Otherwise, you'd be, in effect, stealing his services. So if you can take it from the diagnosis and fix it yourself, pay the $89 and Godspeed. If not, pay the guy for his work, and if you don't like the prices at this place, take your car elsewhere next time.

Dear Tom and Ray:

You wrote recently that different-colored coolants (regular and long-life) can be mixed without danger. Your info might be accurate regarding GM and Toyota coolant, but as a Volkswagen service manager, I can tell you that it's not true with Volkswagen bright-pink "lifetime coolant." The pink G-12 coolant, in use since 1996, is chemically different from the old blue or green G-11 VW coolants. When these two mix, there's a chemical reaction that causes the coolant to "gel" and turn brown in color. The coolant will get so thick that it can't pass through the cooling passages and will cause an engine meltdown.

-- Will

RAY: We've been told by experts that long-life (organic) coolant and regular coolant can be mixed and the only negative result will be shorter life of the coolant. But Volkswagen disagrees.

TOM: VW put out a service bulletin warning against mixing its own coolant (G-12) with its older, G-11 coolant. We'll have to take the company's word for it, as we're not willing to sacrifice any of our customers' VW engines to test the theory. (Well, there is that Mrs. Beaseley . . .)

RAY: Thanks for the correction, Will.

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(c)2002 by Tom and Ray Magliozzi

and Doug Berman