Question about 1991 Mercury Grand Marquis

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Air conditiner vacum

Changed of position of air

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I can not understand your question. do you want to know how to change the place where air comes out or it does not come out at the place where you want it to come out?

first of all, the flapper are vacuum controlled. you need a vacuum source which comes from the engine. it could be trace by a black plastic hose coming from a vacuum canister that goes inside the car thru the wall near the air conditioning evaporator. this hose went to a valve that directs the vacuum to each vacuum valve that is attached to the flappers. as you turn or slide the switch, it opens a vacuum line to each valve to change its position. either close or open. if everything is not changing wherever you place the switch, it could be a bad source of vacuum. a broken line from the engine to the switch. if it does work on some position and would not on other position, then it could be the switch itself. sometimes there is just a leak on the valve or the hoses are just not tightly pressed on the switch.

i hope i was able to help...

Posted on Jul 08, 2008


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