Hey thanks fellas, you were right bad tire, left rear had bulge. Great to have this kind of support for us rookie MBZ owners.

Finally getting cold here in NM, tried heater last night, only blew cold. Did search and learned about the monovalve. Unplugged it, tapped it with screwdriver, and guess what "hot air". Looks like I'am due for new monovalve.

Now if I only can figure out that clunk from rearend, happens at times with or with out load. Might be rear axle?

Thanks for your help..
Andy

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83 300D 169K (Mine)
86 F250 4X4 6.9 (Mine)
05 VW Passat TDI (Wife's)