1982 300TD

So all of the sudden I've got no a/c, and weird vacuum issues. The power locks aren't working, and shutoff takes about 30 seconds. I checked for vacuum pressure coming off the main line, and it's good (it better be! I just rebuilt that pump!) Not a huge deal on that, it seems like just a leak I have to track down.

The real pisser is the a/c. It was working fine yesterday. Today, only heat and no center vents. Is there a way to test my climate wheel for proper operation? Also I had noticed when the heat was on, I could hear a faint hissing by the passenger knee plate (normal!??) and when I'd roll the climate wheel to MIN, the hiss would go away. Now, the hiss stays, and I've yummy hot air blasting in my face.

The compressor is running just fine. Hmm... center vents might start functioning after I fix my vacuum leak.... Thoughts??


One more quick tangent. I've got the wagon. I noticed something I alien to me the other day. In the rear of the interior, just in front of the spare tire is a little black metal tank with 3 braided lines running into it. WHAT THE HECK is that thing? I didn't really have time to investigate/trace it.

Thanks a million.

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'90 300SE --- 173k miles --- (Odometer just stopped working!)

'85 Cali 300D --- 193500 miles --- (Second one) Sold Nov '10

'82 300TDT --- 236,xxx miles --- (My first one) Sold July '09