1. I paid by credit card, can I call credit card company to refused to pay this money?---I would say yes. Check with you credit card campany.I don't think it will cost you any fee even if you loose, but check with them. They will fight it for you. If you are lucky, you win, or at least part of it, and save you some money. You should write down everyting in detail, Item by item on the invoice, to help them fight it for you. There are 3 things for you to fight: 1) They sold you unwanted, unnecessary service. For example: Were the windshield blades good? if so, state on paper---that is to say, they did things unnecessary. While they threw in alot of unneeded service, they missed the necessary maintenace--tune up ( double check this with your owner manual -- if your manual says it needs tune-up at 90k, then you are lucky--use your manual as proof that they did not know what they were doing.2) They damaged your car while performing the service. 3) Overall, poor service--when you first noticed the noise, they ignored your complaint, brushed you off. Then, later on, when the noise did not go away, as they promised you it would, they refused to back up their onw words. Their poor quality service put safty harzard on your car, therefor endangered you and your pessangers' lifes! --I like this sentence :). You need to write everything nicely, state the facts. Do not use angery words. have a American friend check it for you.
2. for my car 90k, I need do a tune up? the major maintenance does not include tune up, do you think it is better to go dealer?--No, unless there is a problem. Never go to a dealer unless is warranty repair. They charge 2 times more than local repair shop.
3. what kind of repair shop is better?--No body knows. Some are more honest than others. Go to a relatively decent looking repair shop that is close to where you live, so if there is a problem, you can go question them.
If you go with a friend who knows about cars,the repair shop will less likely cheat you.
Let me know if I can be of any more help... I would be glad to help!