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1998 Mercury Mystique Repair Question


Topics covered: Engine, Door, Floor.
Mileage: 90,000 miles.

Asked on November 30, 2011

I have 1998 Mercury Mystique Ls the heat and a/c blow only out defrost why, and how do I fix it.Thanks!

It makes no differance to what setting I put it on,panel,vents,floor it just blows out defrost vent. If you will please explain why it does this,and what I have to do to fix problem. V6 1998 Mercury Mystique LS 2.5
Avatar Asked by Ronski

Answer

Replied on November 30, 2011

The vent doors are actuated by engine vacuum. Check for vac leaks under the dash and the supply hose from the engine. If you are lucky, you may hear a hissing sound with the engine running.

Tiny Answered by Jacobandnickolas (expert)
57,318 answers provided