You may want to check the steering boot; mine is shot and a nice stinky undercar breeze eminates from the nether regions of the dash unless the ac is on normal. Mine is readily visible from the top of the car (under the hood) where the steering shaft passes through the firewall.
-Tom

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RIP "Betsy" (Oo=*=oO)
'96 E 3 2 0 (W 2 1 0) M 1 0 4 (Totalled)
Spaces in sig so as not to screw up the SEARCH; every time someone searches for that MB they don't want my sig!

2004 Audi A8L
'98 VW Passat 1.8T 5M
'87 Alfa Romeo Milano 2.5L 5M
'67 Impala convertible, 327cid