[Brutus]

The exhaust leak has been fixed.

I had the car in the shop for a week and after $800 it runs poorer than when it went in.

I'm questioning the under drive pulley and the fan. When the fan is set too low, it runs after shut off and kills the battery. If it is set too high, the engine temp fluctuates - and when it gets hot, the a/c doesn't blow cold. As soon as the temp goes back down, cold a/c again. Can anyone explain this?
Maybe the under drive pulley is turning the water pump too slow? Electric water pump?

Also the car has a real problem getting boost and will not go above 7 or 8 lbs. and really struggles to get to higher revs (above 5000 rpm).

At idle it has a stumble about every 5 seconds or so and that stays as the revs climb.

The mechanics checked the entire system for leaks, replaced the waste gate, replaced the plugs (that were only a month old - what could kill the plugs so quick?) and could not get the boost to go up.

There is also a pretty good resonance at 3400 rpm that is new and feels very weak. It sounds and feels like drive line not exhaust.

When I brought the car in i could get 12-14lbs boost no problem. I just wanted it fine tuned.

when i left the shop he said maybe i need a new turbo so i agreed to purchase a set up, inter cooler and all, and have him install it.

On the way home after getting gas the battery was dead. Fans kept running.

I called him and he suggested that maybe i need a new motor.

I really need some sound advice here. I just want the car to run at it's best and I'm having a hard time getting that done.