Car Problem Reports

Dodge Ram Van B250 HVAC Air Flow Switching to Defrost When Accelerating

Dodge Ram Van B250 Problem
17 Reports
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Model Years Affected: 1990, 1991, 1992, 1993, 1994

Average Mileage: 142,483 mi (86,555 mi - 251,000 mi)


The AC/heater (HVAC) system may unexpectedly switch to the defrost mode when accelerating. This system is operated by engine vacuum and should be inspected for any vacuum leaks if this problem develops.  There is also a revised vacuum check valve available to address this concern.

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