Re: Strange HVAC behavior

[DeWitt Harrison <de@aztek-eng.com>]

On Mon, 17 May 1999 07:41:04 -0400, Brian Armstead wrote:

>Fellow Listers:  When I accelerate in my '89 200q with the A/C on, the
>air will switch from the dash vents to the floor vents.  Switches back
>to dash vents once I stop accelerating continue cruising.  Any BTDT's???

I do believe you have a bad check valve allowing HVAC vacuum system
to become pressurized when IM pressure goes positive. You may find
that the vacuum operated diff lock also releases under that condition.

DeWitt Harrison
Boulder, CO
88 5kcstq