Question about 1992 Dodge Ram 250

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Max setting on a/c. front vent ok,accelerate

Max setting on a/c. front blower air vent ok,accelerate demand pwr,all of the front air, goes to the defroster vent.until decelerate then air comes back to front vent. Mechanics thinks its a vacume leak, but where should start to check. is there a diagram for the a/c

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Sounds like your mechanic is definitely barking up the right tree there!
Check the vacuum hose leading from the engine through the firewall to the underside of the dash where all the vacuum motors for your heater controls are. It is common for this hose to be cooked up and split from engine heat. Hope this helps.

Posted on Sep 30, 2009

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Check under the hood with the engine running, you may be able to hear it. Sssssssssss.

Posted on Sep 30, 2009


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