Block Heater?
 

I recently installed a block heater in my Tacoma for fuel mileage, not for ease of starting. So I was wondering what other people do in regards to pluging in their vehicles for fuel mileage. Do you always plug in your vehicle or is there air temperature (40-50+/- deg F) that you stop pluging it in?

Any amount of heat added to the engine helps reduce post start-up fuel consumption, not to mention wear and emissions.

Mine was installed before the winter, but I intend to use it year-round. In the warmer part of the year I may keep it on for only 1-1.5 hours, instead of the current 1.5-2.5h.

I use mine year round as well. the only time I don't use it is when the outside air temps are expected to be ~140df then I won't need the block heater. ;)

I plug mine in at tempuratures below 10C [50F] and have it on a timer for 90 minutes only, on work days, on other days, I just plug it in about an hour before I leave. So far the things I've noticed are that the cold engine lite goes off 30 - 60 seconds sooner, at -20C, the scan guage WT first drops from about 35C for about 30 seconds then rises to 55C in about 1 minute on the highway. I have not tried to quantify how much fuel I save.

Mine gets started about 6-7 hours before needing the car. Then the big iron lump of a FSP engine gets up to 85-90*F at 15*F outside temperature. And it stays there or higher during my short-tripping mornings for work since the 150 or so lbs of iron making up my engine is thoroughly heat-soaked.

I'll likely use it year-round with reduced times in the summer for better fuel economy year-round.

It only needs an hour or two of plug-in time.

I tried an hour or two, and it raised the temperature to 50*F when it was 15*F out. That temperature plunged rapidly upon engine startup.

My electric bill hasn't noticed much of a change either way. It's a 400-watt Kats coolant heater plumbed into the lower radiator hose on the opposite side of the system from the thermostat.