The automatic climate control of the same era should work the same, at least according to the owner's manual that I have. I also used to have an '82 300D (with the automatic CC of course) and the air shut off feature with the "off" button worked better than in my 240D, but there was still some leakage. I'm tempted to pull out the glove box from my 240D and see if there's a sticking flap or something. I'll probably do that sometime this weekend.

As far as an actual recirculation button is concerned, I think MB didn't put one in the cars until the '86 model year... a very useful feature on congested highways and streets if you ask me.

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2004 VW Jetta TDI (manual)

Past MB's: '96 E300D, '83 240D, '82 300D, '87 300D, '87 420SEL