Mobil 1 should not need to be changed every 2K miles unless you are an extreemly aggressive type driver that's on the turbo all the time. Try some relatively easy things like cleaning the throttle body and running some fuel injector cleaner through a couple of tankfulls. Check for intake system leaks and loose vacuum line connections. You also have the last year that had the bad wiring insulation problem. The engine harness may need some work. Sometimes the oil return line gets plugged up near the turbo connection.