Hiya Uncle Old Duke!!!

Welp, if leaking in the rain, the windscreen gasket, rust at the windscreen pincheweld / pan, or failed gasket at the bulkhead / firewall plates the wire harness bits travel through.

Though if the bulkhead / firewall plates the wire harness bits travel through is leaking, usually happens more so when raining and driving.

Continued moisture intrusion can cause rust. Also, use of anything to kill them microbes gets diluted and the microbe stinky can return.

As with my 1990 and 1991, original windshield on your 1992 245 wagon? If yes, the butyl rubber gasket dries and loses seal. Won't fix itself.

You can remove the interior trim bits around the interior windscreen side to reveal the A-pillars and such. Use a spray, or a pal with a big bottle of the ripple to spray and see if you can find a leak. You can get butyl gasket stuff in a caulk gun, and jam it in the dried up butyl tape gasket and see if that plugs the hole.

The factory butyl tape gasket on my 1991 remains pliable and sticky.

Sometime the windshield is replaced, and some windshield replacement technician does not remove the butyl tape (or they break paint removing the old windshield, causing a rust-though in time like on my 1992). If so, you'd need a wind shield replacement.

If I was near you, I'd bring some of the muscatel. Or maybe like Rumpole of the Bailey, some cheap claret wine as you like.

Hope that helps.

Questions?

Bland Pizza Boy (on a Monday).

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