Weel the othe night I popped both my head gaskets beating on the car. It looks as though the heads lifted again because the gaskets where blown out from the water jackets to the fire ring with no burn marks on the ring. I had ARP head bolts instead of head studs and it cost me. ( 12psi of boost @ 5500 ) Any how I had to limp the car home as I was only a few miles away. The car never over heated but was blowing major amounts of white smoke. I was wondering if the fact that I drove the car for a few miles in that condition if it would have done anything to the 02 sensors. The sensors are less than 2 years old and I didnt want ot have to replace them also.