 The Car Doctor. I have it out of the canister now yet, and so I can apply pressure or vacuum to it, and it does respond. Okay, so we've got to say then that the sensor's working correctly. Welcome to the radio home of Ronananian, The Car Doctor. Since 1991, this is where car owners the world over turn to for their definitive opinion on automotive repair. If your mechanic's giving you a busy signal, pick up the phone and call in.