Question about 1983 Mercedes-Benz 300-Class

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My A/C blows out throught the defrost and dash vents all the time

I have changed the module and have even opened the dash and manipulated the lever to the baffle manualy. It does ot make a difference.

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You have a vacuum issue. I beleive that is the default position., Check your green vacuum source line at the L side of the rear firewall (in engine compartment). There are actually 3 vacuum lines. green a/c, yellow central locking, black shutoff valve(deisel only), red is for your heater valve. any one of these systems can leak and have an adverse affect on another system. it is a great place to isolate a system and see if another comes back to life. hopefully this will point you in the right direction.

Posted on Jul 15, 2009

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