check engine light on 2002 Toyota Camry

engine check light remains on. gas cap has been replaced. Is this a sensor issue,or canister,or? What checks can I do before taking it to a shop? Cost est.?

1 answer
Your car has on board diagnostic capabilities. Once the "Check Engine Light" has turned on the computer in your car stores codes that indicate what it sees wrong. A scan tool that is OBD2 compatable is needed to figure out from here what is wrong. If you have the code number we can tell you more about what is seen to be wrong with your car. The code number will read something like "P0420" but again a scantool is needed to go further.