check for vacuum leaks first.
also have it taken to your nearest dealer for a check on the computer control unit. So they can diagnose if is vacume or idle settings. May be something as simple as a quick turn of the idle control sensor.
2004 Mercury Grand Marquis LS Ultimate
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Maintenance & Repair
My 2007 mercury grand marquis is running hot it used to cool down when pick up speed but now it goes hot and then shuts off????
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Maintenance & Repair
About a month ago my 1998 Mercury Grand Marquis started running rough after I pumped regular gas at a Chevron Station. As the car has 67,000 miles I took it to Sears Auto Center to have the spark plug...
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long story short. I went prison for three years. Got out. When I got my car back, it started by key for the first couple starts of the day. After those first couple initial starts, I have to spray ...
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Maintenance & Repair
I have a grand marquis 1998 with about 169,000 miles. It uses to shake bad when it changes gears before I replaced my oil gasket that had my number 4 spark plug covered in oil. After I got my oil ...
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