Question about 2003 Mercury Grand Marquis

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I have a 2003 Mercury Grand Marquis and it's idling rough and when I put into gear it hesitates and the battery almost dies until I step on the gas pedal.

It recently overheated and I had to change out the thermostat. It starts up OK and I drove around after but now it stalls and has a rough idle. When I place into any gear it immediately loses power and the battery light lights up.

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Sounds like a bad alternator. You can bring it to most car parts stores and they will check it for you.

Posted on Nov 18, 2014


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