2004 Intermittent Check Engine Light

I have a 2004 Taurus with the 24V DOHC engine. The check engine light has come on about 5 times in the past year. When it comes on, the car is running bad (no power), exhaust sputtering, and the Ave MPG reading on the dash drops to around 13.5 mpg. If you pull off the road, shut the engine off then start it back up, it runs fine again. In 2 to 3 days, the check engine light goes out and this probably won't happen again for several months. I took it to a car parts store that reads diagnostic codes for free but they could not get a link with the car. Just wondering if anyone out there has experienced this or could give me a clue. :frown:

Does the 2004 Taurus DOHC have the Coil on Plug (CoP) configuration? If so, you may have a coil or two failing. Is it still under warranty? With the exhaust sputter and MPG reading dropping, it should be considered an emissions-related problem and may have a longer warranty than the drivetrain.

-Rod