Plugging in a gasoline car (does block heater energy consumption offset fuel saved?)

[Ryland]

Most Christmas tree light timers can handle 500 watts so having the heater switch on at 5am or around the time that your alarm clock goes off your engine should be warm by the time you need to leave, lower energy use and longer block heater life then leaving it plugged in all night.

[Neddy Seagoon]

I would have to second the statement that Engine wear is a big factor on a cold start. The engine goes to a fast idle with extra fuel being injected into the cylinders thus washing the oil off the walls, plus it takes a few seconds for cold oil to start circulating around vital engine parts.
With my block heater on for 2 hrs there is no fast idle and a lot less fuel being wasted warming up a cold engine, plus I get heat into the cabin faster.
This is one reason I hate remote car starters, wear on a cold engine and massive amount of fuel wasted.

Neddy Seagoon.

[puddleglum]

I agree that engine wear is a major factor that most people ignore. Most info I've seen says 90% of wear takes place during warm up. I've become a firm believer in block heaters, even if the plug in cost is higher than the fuel savings. I'm finding, though, that my OEM 400w EBH is not enough in really cold weather and I think I need something bigger. I suggest that anyone thinking of installing one, make sure you get one large enough to do you some good. I only see about a 20C/36F temp rise in a 2.4L engine.

[TomO]

Originally Posted by Ryland

Tomo, Any idea how accurate that cold engine 25mpg figure is? I can't remember if you have an MPGuino or not.
And what type of engine heater do you have? oil heater, coolant heater, stick on block heater?

That Cold Engine 25mpg is just a number I pulled since the car is supposed to get nearly 40mpg city (fully warmed). I figured it'd get more than half of the City mpg as it warmed.

I have an MPGuino.....it's still sitting in two major pieces since it failed to work properly when assembled. There were some solder bridges that I didn't check for on the pre-soldered IC. They have since been cleaned up but I haven't stopped by Radio Shack to get some more pins to re-connect the LCD to the main board.

I used the OEM style block heater which is a screw in type wher ethe engine block coolant drain is located. Pics of the installation: HERE

[Ryland]

I just got my engine block heater for my Civic VX in the mail! bought it from Majestic Honda for $29.40 plus shipping ($12, but that was with other small parts as well), it came with 5 pages of instructions, mostly on ideal wire routing including a page on removing the front bumper so you can properly hide and secure the cable.
It will be a while before I get a chance to install it, but it should be a nice addition this winter.