Q:Hi James. I keep having an oxygen sensor fault code for a lean exhaust with my '97 Corvette. I've taken the vehicle to the dealer several times but the problem keeps recurring. I would like to try ...

A closed loop control system for regulation of engine air-fuel ratio at the stoichiometric value is required for effective operation of a three-way catalytic converter. System performance depends ...

Between the two tests I tried a few things including cleaning the idle control valve, Italian tune-up, new plugs, etc, but the second set of results are worse. The first garage wanted to replace both ...