I’ve been told that it could be the climate control unit but most likely it’s the vacuum pieces under the dash that have gone bad. They have a plastic diaphragm inside them that go bad over time. Make sure your climate control unit is good, then look for the diaphragm devices to see if they are still working.

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Professional greasecar installer
Austin TX


98 Jetta TDI with grease car kit + veg-therm (totaled)
87 MB 300SDL running on B99 / greasecar kit + 30 fphe
www.austingreaseguys.com