I need to reset check engine dash light in 2004 deville. dealer has told me what is going on and i choose not to repair at this time. how do i make the check engine light in dash

It depends on the error code(s) being reported. A very common one (P0457) is that the engine computer thinks the gas cap is loose. The gas filler neck often develops rust holes which cause this code, fix is repair usually quite easy, or replace. There are many other error codes. Look around your area for a Subaru shop other than the dealer. Your problem fix may much simpler and cheaper than the dealer, who often give the most expensive, worst case, repair options.

Being a Cadillac/GM. Do a reset for the security. Turn the key on for ten minutes, off for thirty seconds. Try to start. There is also a relearn. ten on, thirty off, three times, then try to start. other wise, dealer...

Hello: The check engine light is telling you there is a problem. To diagnosis and repair you need to go to Auto Zone, Advance Auto or O'riely auto parts stores and have the code read. Then you will know what is causing the problem. You could also go to a GM dealer. There are about 100 things that can cause
to come on.

They are sluffing you off... have it scanned somewhere else and find out what is wrong then go back and make them fix it.

Check your timing

Make sure you are using premium gasoline and have the car scanned (OBD2) most likely you will need to replace O2 sensor.

You can check the trouble codes (DTCs) with a code reader and go from there, but unless you have the necessary repair skills, you should leave it to a dealer or reputable repair shop.

Buy, borrow or rent a code reader. PLUG IT IN UNDER YOUR DASH. Follow the instrutions'and it will tell exactly why the light is comming on. Like your dealer should have.

It's not the t-stat they read the code wrong go to checker or any auto parts store and use one of there code readers, I had a shop tell me the same thing. the codes are right next to each other Also you don't need to remove engine to do this job you just take off the alternator it's right under. My shop quoted me $300 for a $25 dollar part