I just recently bought a 2002 VW Jetta 2.0 with 140000miles on it and I only put 640 miles on when all of the sudden while driving I could barley accelerate. The rpms will get up to around 3000 and my car will make a loud grinding/rattling type noise. At first I thought it was the catalytic converter so I disconnected the exhaust and it still ran the same way. Then I thought maybe Mass Air Flow Sensor so i disconnected it and it ran the same way if not worse. Then I thought maybe the fuel filter or air filter, I replaced both and still runs the same. The weirdest thing about this car is I unplugged the coil pack and the car still ran. Everyone I have asked about that has never heard of it in a gasoline engine.

I took my car to a german auto shop and paid $85 for a piece of paper with codes he pulled. 1 was for the Mass Air Flow Sensor which I had disconnected 2 was for Air Intake Temp Sensor 3 Was for Up Stream O2 Sensor but I probably caused that by disconnecting the exhaust from the header 4 was for the Camshaft Position Sensor. He insisted that the Mass Air Flow Sensor and O2 Sensor were the problems. I'm hesitant on that because if its they're not that problem I cannot return the parts after installing.

I hope someone out there can help me. Thanks.