I had a mechanic who just replaced the valve cover gaskets, two places, for my 2000 Toyota Sienna. He charged $280 for that. The engine light now comes on, and he said that is due to a exhaust manifold leak, even though the light was not on before I brought it in. But, I can't really blame him, because I have always heard the popping kind of noise in the morning when I start the car, that is, when it's cold, even before bringing it in to have the valve cover gaskets changed.
I would like to know:
1. How much it's typically cost to replace the manifold gasket?
2. What other steps/heads-up should I watch out for, for example, new nuts and bolts must be used when replacing the gasket?
By the way, in the past, I had a bad a mechanic, and somewhat dishonest. He did the timing belt and water pump replacement, and I am wondering if the exhaust manifold has to be removed to do the timing belt or water pump replacement. If that is the case, I am thinking that the guy didn't put back things properly.
It's so hard to find good/honest mechanic. There are some, but so hard to find one. Advice on how is also appreciated.