Intensified Federal emissions laws forced the auto manufacturers to implement new emission control devices on all vehicles sold in the United States. Cadillac, among others, uses a warning system to alert the driver of a loose gas cap. Operating a Cadillac with a loose gas cap allows gas fumes to escape into the atmosphere, adding to the pollution already in our air. If your Cadillac's gas cap warning light illuminates, there are a few things you can do to check for the cause and remedy the situation.
Remove your Cadillac's gas cap. Inspect the cap for damage, such as chips, cracks or warping in the plastic or the rubber gasket; replace the cap if you note any.
Inspect the gas filler neck for cracks, chips or dents. Reinstall the cap until you hear it click twice.
Start the engine and see if the gas cap warning light has turned off; if not, move to Step 4.
Look underneath the fender where your fuel filler neck leads to the gas tank, using a flashlight. Inspect the filler neck and fuel lines for any signs of damage or wetness, or any loose lines.
Purchase and install a new gas cap. If the light still does not turn off, drive your Cadillac to a certified technician for proper diagnosis and repair.
