03 sunfire, check engine light is on runs like it is missing. As I drive it will flash but when it comes back to an idle the light is constant again.
Time to have the car scanned, stop off at your local auto parts store, most will do it for free.
I would not drive it any more than you have to, when the light is flashing. That indicates potential harm to the expensive Cat Converter. Most common cause of misfire is the secondary ignition, spark plugs and wires.
Not really an answer here, but an affirmation re: my wife's '03 Sunfire (HATE that little black "roller skate"). Same symptoms and a full tune-up remedied the problem. My LAST good GM was a '74 Monte Carlo, 454 engine, all the bells and whistles with a black leather interior. Most GMs since have been CR*P...
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