Block heater, smoking under hood???

[Greg K]

It was minus 30 here this week, but when I plugged in my block heater, wisps of smoke arose from the block near the firewall.
Its probably the first time the block heater was ever used in my 2001 3.5 engine.
Is there any danger of a fire? Or is the block heater just burning off a bit of old oil drips?
Has this ever happened to you?
Should I just let it burn off the old oil?

[Paulaurora]

hmm not sure never had one.