Ok we own a 93 sedandeville and im gonna clean the injection system(professsional kit) and im wondering will this also clean carbon deposits off my oxygen sensors. The kit i use i know cleans catylitic converters as i saved a buddy 400 bucks cleaning his out with this product. My Service Engine Soon light comes on when i use cruise control or stay at one set speed error code is right oxygen sensor. We are getting horrible fuel mileage 10.3 average highway and cityi fueled up 3 times in one week. This weekend i will be cleaning injection system,changing oil and filter, changing air filter, changing plugs, and spark plug wires cap rotor, and fuel filter. What Kind of fuel mileage should i expect after? Car has only 89k on it.