Question about 1998 Ford Escort

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Vacuum goes from vent to defrost when excelarate

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You have a vacuum leak somewhere. When you accelerate your engine vacuum drops. with a leak in the lines going to the heater control head you are not able to hold the spring loaded actuator door in the position you have it set for. The rest position of it is defrost. check for cracks or splits in the rubber vacuum hose that comes from the engine thru the firewall to the heater control head.

Posted on Apr 21, 2013


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Posted on Jan 02, 2017

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SOURCE: Air conditioner blows through defrost vents


Posted on Sep 13, 2008

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SOURCE: when I accelorate my ac vent goes from center

Check the white vacuum hose going to your recirculation door outside under the hood. It is located on the passenger side firewall . The hose becomed brittle and falls apart. I get small vacuum hose and cut into the wiring harness to locate a good section of hose.Put hose to vacuum motor. Good luck.

Posted on Aug 10, 2009

  • 65 Answers

SOURCE: I have a 2000 Ford Expedition with 4.6 litre

yes you have a vaccum leak some where. there is a vaccum cannister attached to the battery tray so it could have corroded something or you have a one way valve that clould be bad on the black vaccum hose coming out of the fire wall goin to the engine

Posted on May 10, 2011

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