1999 Mercury Marquis Rev's up

1999 MERCURY MARQUIS
173,700 MILES • V8 • AWD • AUTOMATIC
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LUCKIE9
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  • 1 POST
In the fall I had a heater core replaced and since then when the heater is on, the car revs up. Recently when it snowed, I let off the accelerator and the car went by itself. The only time it does it is when the heater is on.
Feb 12, 2010 at 10:03 AM
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JACOBANDNICKOLAS
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  • 110,175 POSTS
It is normal for it to rev when the defroster or AC is on. Is that what it does, or is it when the heater itself is on?
Mar 24, 2010 at 11:24 AM