There is SO much information out there now about car repair no one should be a "victim" of an unscrupulous mechanic.
I don't care whether you have a Geo Metro or a Corvette, there's a forum out there somewhere on the internet dealing with your particular car.
CEL (or service engine soon) light on? Limp it to autozone, get the codes pulled, and search. (DO NOT!!!! buy the part that autozone tries to sell you, it may or may not fix the issue, and your mechanic isn't going to appreciate not making the markup on the parts. Damned crooks need to put food on the table too)
Someone has had that problem before, and someone can help you diagnose it. Even if you don't turn wrenches yourself, you can at least get an idea of what the repair is going to be before driving to those thieving mechanics.
Odd noise? Go online, find a forum relating to your particular car, and search. Someone has had that problem before.
All it takes is a little research and you can avoid getting taken advantage of.
As with anything else, forewarned is forearmed.
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