Dear Tom and Ray:

I took my car in because the air conditioner wasn't blowing cold air. I was told there was a leak in the high-pressure hose and it needed to be replaced. Well, 250 dollars later, I had cool air again ... for a few weeks. I took the car back and was told that now my compressor had a leak, and the replacement cost would be 1,200 dollars. I decided to get a second opinion. The second mechanic told me the compressor was fine, and that I had a leaky valve, which he fixed for 80 dollars. Furthermore, he told me it didn't appear that the high-pressure hose had been replaced. I'm upset to have paid 250 dollars for a repair that may not have been done (although I don't know how to prove this). I'm also upset that the same shop wanted to charge me more than 1,200 dollars for a problem that appears to have been fixed for 80 dollars. What do I do if I feel I got cheated?

-- Becky

TOM: Well, our customers usually come back with friends and baseball bats, Becky.

RAY: This is surprising, because most dishonest shops are at least clever enough to lie about parts you can't see. I mean, that was drilled into us at the very first seminar!

TOM: The first thing I'd do is go back to the second mechanic, Becky, and ask him to look again. If he's sure that the high-pressure hose is not new, ask him to put that in writing for you on one of his repair orders. You also can ask him for some help in taking a few pictures of it.

RAY: Then go back to the first guys, and calmly tell the manager that you believe you were charged for a part that was never installed. Say that you're sure it's just an oversight on their part, but you'd like your money back.

TOM: If he's a decent manager, he'll take your complaint seriously, and inspect the car and come to his own conclusion. And you always want to give someone a chance to rectify a mistake. Because it could be just that -- a mistake.

RAY: Right. Maybe you heard incorrectly, and it wasn't the "high-pressure" hose they replaced. Maybe he had a crooked employee whom he just fired for claiming to do work he didn't do. Or maybe they buy high-pressure hoses that are "distressed," like kids' jeans that come with holes pre-torn in them (OK, that's a stretch, but we're trying).

TOM: But if the manager denies that it could have happened, tries to intimidate you or just refuses to help you, then you make a few notes about your conversation with him, and file a complaint in small-claims court.

RAY: With the evidence you have -- a written, professional second opinion and the photographs -- you should prevail in court and get your money back.

TOM: These days, the best way to warn other people about dishonest businesses is on local Internet sites that offer customer reviews, like AngiesList.com, for instance. If a repair shop has a number of poor customer reviews attached to it, people will start to avoid it.

RAY: We have a similar service on our Web site (www.cartalk.com), called the Mechanics Files. And by the way, these sites are also good places to PRAISE good businesses, to encourage people to patronize honest and talented local service providers.

TOM: The final thing I'd suggest is to keep an eye on your air conditioner and make sure the 80 dollar repair holds. If it starts blowing warm air again in a few weeks, and it turns out you do need a compressor, you may have to reconsider everything, Becky.