What is fair and right, when auto mechanic doesn t fix it first time, but charges you?

What is fair and right is that you pay him what he is due for the repairs that you asked him to perform. The problem is what you asked him to do was not going to fix your problem. You did your own diagnosis, supplied the parts, he installed them. The issue is you didn't ask him to fix the problem. You asked him to install parts. The part he did he performed well, and properly. You deserve what you got. Ask the mechanic to find the problem and fix it next time. Don't second guess it, or you'll continue to be dissatisfied with the results.

The reason it wouldn't start is likely the battery or the alternator not providing sufficient cranking power, or not charging the battery, for the starter or switch to work properly. If you had asked him to check out the right things, and fix the problem, you wouldn't have been in this position.

He didn't try and fix the problem, he only did what you asked and that was to install a solenoid that you provided. If you agreed on a price and instructed him to install wings on the side of your truck you can't blame him if it doesn't fly.

YOU gave him the solonod and he installed it..Isnt that what you wanted? If you came to my shop id throw you out..when yyou go to a restrant do you bring steaks from the supermarket? you are a bad custumer

He did as asked. You paid for his time.