2002 Chevrolet Silverado 1500 Q&A
2002 Chevrolet Silverado 1500 Question: bad gas milage
Assuming you are checking your mileage at highway driveing it could be several differant things that could cause a decline. A lazy O2 sensor or a coolant thermostat that is staying open causing engine temp to run lower are things I look at first. Air filter or dirty mass air sensor can cause low fuel mileage. Of couse the basics should be checked first but cannot rule out a brake caliper draging or transmission that may not going into overdrive. Im sure someone else will comment on things I have failed to mention. - milesauto
My 2002 Silverado went from 20 MPG to 16 MPG as soon as they started adding 10% ethenol to the gas. - leroygeddis
About 35000 miles, check engine light came on. Dealership repaired. Stated a sensor on top of gas tank went bad. I have about 52000 miles now and the engine light has come on again. Engine runs fin...