Ok guys, plugged my block heater in tonight, went inside for an hour, came out to get something out of the cab and I could hear a noise from underhood. Opened the hood, sounds like a humming from the drivers side of the block. Unplug the heater, it goes away after a few seconds. Plug it in, it comes back after a few seconds, needless to say, I left it unplugged tonight. Any thoughts, this has never hummed before, especially from the drivers side of the block.

 

Why are you plugging it in. Surely it can be that cold there right now. It is probably your heater could be going bad. Just see if the heater warms the motor still.

 

I plug it in because its 20 degrees at night. It snowed yesterday. Anybody have anything?

 

the block heater is on the passenger side of block.

 

Yeah, I'm aware of that, thats why the mystery of the hum from the drivers side when its plugged in. Thought I explained that.