535i Cold Start "Moaning" noise.

[mcd@xxxxxxxxx]

OK everyone, this is a weird one. I've got an '86 535i with about 150k on
it. I'm the second owner, and only had the car for about 3 weeks. So far
everything's been great. But in the last week, I've noticed that upon cold
starting, I hear what can only be described as a "moaning" noise emenating
somewhere near the firewall. It happens once - lasting only a couple
seconds, and doesn't reappear untill the next cold start.

Has anyone ever heard this before? Thanks for any input anyone can provide.

mcd

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