dude i have never heard of warped pistons in my life, did the motor overheat?

 

Could be a very easy fix. Go thru all basic checks

 

are you crazy!!!! a whole new engine before you even know whats really wrong with this one???? You must have money to burn.
It could be a simple error within the vacuum system that creates a bad idle (which was the first problem, before it got worse)....
Make yourself a proceedure to find out whats wrong with it, and go through everything one by one... It could be something that will cost a few hundred $$$ to put right, but youre taking about 9000!!!!

 

Now I have another one to add to the list....just when i thought bad exhaust bearings was a good one......Did he mention anything about a flux capacitor??

Sounds to me this mechanic is really taking your brother for a ride. But it does sound like you need a good tech to check it out. From what your telling us,your symptoms sound like a vacuum problem or the charging system/alternator.

Has he had anything done recently to the vehicle?

 

You have simple problems, and are being ripped off.