Block heater on 2003 silverado with 4.8l

[hamms-scooter]

I plugged in block heater to help with efficiency in short trip driving in town. Well I don't hear a hiss sound at all and temp gauge didn't go up at all after starting either... How can I check this thing? I have good power to the cord.

[Dozer]

Go plug it in when its dark out, you should be able to hear/see a spark when the plug and extension cord connect. I dont think a block heater is going to heat it up enough to help you with effciency, there only 400watts.

[Ufatz]

Well, I gotta say, after decades of using block heaters I don't recall ever hearing a "hiss sound" and if the OAT is that cold it is going to take a while for the temp gauge to start up.

Don't you notice a difference when you start the truck after a COLD night? Should fire off quicker without as much cranking.

A functioning block heater should be a mandatory part of a vehicle in MN.

[RebelSS]

I remember some of the old "thermo-pump" tank heaters as they were called, heaters that were in your heater core hose doing that, but not a block heater that's in the water jacket core plug of your block....

[hamms-scooter]

It has a big battery and even on the coldest mornings it starts well. I just wanted to make it easier on the rig. My little car I had had a block heater and it warmed it up very well. Been a while since I had a V8. Going to try it out again. Everyone I have had made a hiss type sound.

[hamms-scooter]

I tried it again and it fired up.