* Get the diagnostic trouble codes (DTCs) read: This can be done in a few ways:
* OBD-II scanner: Buy a relatively inexpensive OBD-II scanner from an auto parts store. Plug it into the car's OBD-II port (usually under the dashboard), and it will read the codes. Many scanners also provide descriptions of the codes.
* Auto parts store: Most auto parts stores will scan your car for free. They can tell you the codes and often give you an idea of what might be wrong.
* Mechanic: A mechanic will have the tools and expertise to diagnose the problem definitively.
Once you have the DTCs, you can:
* Look up the codes: Many online resources (like websites or repair manuals) allow you to look up the DTCs and get information about the possible causes.
* Consult a repair manual: A repair manual specific to your year and model Cutlass Supreme will provide detailed troubleshooting information.
Possible causes (this is NOT exhaustive): The "Service Engine Soon" light can be triggered by a wide variety of issues, including:
* Loose gas cap: This is a common and relatively inexpensive fix.
* Oxygen sensor problems: These sensors monitor the exhaust and can trigger the light if faulty.
* Mass airflow sensor (MAF) issues: This sensor measures the amount of air entering the engine.
* Spark plug or ignition coil problems: These are essential for combustion.
* Catalytic converter issues: A failing catalytic converter can trigger the light.
* Other sensor problems: Various other sensors (temperature, pressure, etc.) can malfunction.
Ignoring the light is NOT recommended. Continuing to drive with a problem could lead to more extensive (and expensive) damage. Get the codes read and address the underlying issue as soon as possible.
