just got the Bonneville back from the dealer. Luckily the extended warranty did cover the cost. (which is a great thing!) Looks like the air pump was the culprit. Who woulda thought it. The dealer even washed the ca for us and cleaned the interior. One thing I did notice however was the average MPG when we took it in was 29. When we got it back and I drove it home it read 12 MPG average and the gas tank was 1/4 of a tank lower than when we took it in. I think someone was having a little bit of fun with the supercharger.