Here in southern new mexico we had some rain and cold air move in the other night. It was into the low 60's on the way home from town that night. Normally the TCH would easily go into the EV Mode but that night the engine ran all the time, the entire 8 miles home.

The next night we went to town again. This time it was humid but warmer. I thought the humidity would make it harder to get into the EV Mode.

I was wrong, It went into the EV Mode just as easy as on a warm, dry night. The temperature was 73 degrees during the drive home.

With the cooler months and Winter coming on. I would suggest anyone living in a cold north area might order their TCH with an engine block heater. It definitely helps pre-warm the engine if you plug it in 2 to 3 hours before starting the car.

I tested mine the other night when it was cool outside. An hour later, the scan gauge showed the engine at 125 degrees before starting the car.

 

Very interesting.

Here in subtropical Houston, most folks have not ever heard of a block heater. But I discovered them quite some time ago while working in Alaska and Canada. At the time, it occurred to me that there would be a fuel and $ savings benefit to using one of these for engine warmup in any climate. ICE's burn a lot more fuel when warming up. And the use of gasoline burned in the engine for the purpose of warmup is a pretty uneconomical thing. There would be an opportunity to save some fuel and $ by using an electrical heater.

Percentage-wise the savings would be greatest for short trippers like me who do a lot of their driving with the engine cool, but on an absolute basis the savings per cold start trip would be the same for everyone.

In the case of the TCH, it occurs to me that the opportunity for savinge is even greater (as Jimmy's experience reported here confirms). This is so because the TCH sometimes runs the ICE for the sole purpose of warming up the ICE even in situations when the ICE would othewise be shut off (i.e., when sitting at a stop light before the engine is fully warmed up or when making a cold-start, 2-mile, trip to the convenience store which could otherwise be done strictly in EV mode.

This brings up several questions.

Jimmy:

1. If you had let the heater run longer, could you have gotten the engine even warmer?

2. If you had done this test with a much warmer outside temperature, could you have gotten the engine even warmer?

3. Is there a limit to how hot an engine temperature can be achieved with the heater?

4. Is your heater a "block heater"

5. Was it factory installed or dealer installed? Or aftermarket?

Anyone:

6. Has anyone had a block heater installed in warm southern states (particularly Texas)?

7. Has anyone had a dealer in the Houston area installed one (say with the plan to drive to a frigid climate for a ski vacation for example)?

8. Has anyone moved to the south from frigid regions with a block heater in their TCH and tried jimmy's test?

9. Does anyone have experience with an aftermarket block heater, or aftermarket engine heater of any kind installed in a TCH?

Thanks for any info.

Jack

 

One of the primary purposes of block heaters is to warm the oil so that it flows easily through the engine upon startup, reducing the amount of power required to crank the engine and preventing excessive wear at start-up caused by insufficient oil flow.

The ICE on the TCH also runs to get the exhaust system components such as the catalytic converter up to temperature so that they can properly process the emissions from the engine. Pre-warming the engine itself probably would not help with this.

 

This brings up several questions.

Jack

Jimmy:

1. If you had let the heater run longer, could you have gotten the engine even warmer? Depending on the outside temperature. If its 50 degrees then 2 hours block heater may be enough. If 30 degrees about 3 or so hours may be in order.

2. If you had done this test with a much warmer outside temperature, could you have gotten the engine even warmer? Someone in the forums said, the block heater runs the engine temp up about 50 degrees above the outside temperature. Example, 75 deg + 50 deg = 125 ice temperature. If the outside temp was 30 deg + 50 deg = 80 deg ice temperature.

3. Is there a limit to how hot an engine temperature can be achieved with the heater? I don't remember ever seeing it much over 125 degrees on the scan gauge. That's near 1/4 scale on the TCH temp gauge.

4. Is your heater a "block heater" Toyota called it a Engine Block Heater. Their are two, the one for the Camry is a little different from the Prius.

5. Was it factory installed or dealer installed? Or aftermarket? My dealer here in the desert was not familiar with the term block heater. I called a dealer in North Dakota to find out where our local toyota parts could get one. They gave me the name of a large toyota parts distributor in Los Angeles. I passed this on to my local toyota parts. It came in about a week later. The block heater cost about $39 plus tax.

I read somewhere the heater draws about 300/350 watts of electricity. You put this heat transfer grease stuff on it then slide it into the right rear of the block. Once it's seated it has a clip that locks onto the firewall side of the block to hold it in place. The wire routes up under the air cleaner housing then the plug comes out out somewhere behind the cars drivers side headlamp.

Jack, I used to drag race out of Dallas when I was young and enjoy even at my old age of 68 doing a little mechanic work. I found some picture instructions in the toyota forms. The install is rather simple. The problem is that it took a about a hour to removing the air cleaner housing and then reinstalling it. Although I have slowed down good bit.

It seems like toyota quoted me $90 per hour labor to do the installation. They were iffy if it would take over one hour. I decided then to try the install myself.

I find with the heater the car heats up in one mile during the winter. Before the block heater it took 2 miles. On a really cold 25 degree day before 3 miles but with the heater about 1 1/2 miles.

We all know a cold engine runs the injectors rich till the engine reaches operating temperature which can hurt the gas mileage.

 

Looking at car book prices in the early 60's, I noticed that the engine block heaters came standard on cars in the northern states. This was back before synthetic oil and the thinner 5W or 10W dino oils were available. Back then 30W was about all you could find for years. Then someone came out with a straight 20 weight oil. Later, EON from Houston and also Amsoil came out with a 30W, then 20W and s few years later a 10W synthetic.

Mobil created a fantastic 5 weight synthetic oil for the military in Alaska where they had to start engines in sub 50 to 60 degree weather. About a year later Mobil started selling their synthetic to the public. Many years later they reformulated it and offered a 10 weight oil. In the mid or late 70's the synthetics went multiple viscosity following the lead of the dino oils.

Over the years both the dino and synthetic oils have improved greatly.

 

Many thanks to Tom (TBONE526) for reminding us about this catalytic converter heating business.

This really underscores one of the possible benefits of electrical pre-heating even in temperate climates.

I mean, think of the irony. Say I'm starting out with a cold engine on one of those trips to the convenience store with sufficient battery charge to make the whole trip to the store and back without running the ICE at all. Now the car would choose to run the ICE for the sole purpose of heating up the catalytic converter so that the converter can do a good job of cleaning up the exhaust of the engine which is running only to heat up the converter. What a senseless waste !!!!!!!!!!!!!

Just maybe we could cut a lot of this unnecessary engine running if we merely were able to start up with a warm engine without having to burn gasoline to get the engine warm.

I will soon do a practical test of this idea.

 

Many, many, thanks to Jimmy for the very full and most useful answers to my first 5 questions, which were directed to him.

These answers and also the post from Tom have truly piqued my interest in the concept of beneficial use of the block heater in warmer climes.

So, I remain eager to hear the answers to the remaining questions.

Anyone:

6. Has anyone had a block heater installed in warm southern states (particularly Texas)?

7. Has anyone had a dealer in the Houston area installed one (say with the plan to drive to a frigid climate for a ski vacation for example)?

8. Has anyone moved to the south from frigid regions with a block heater in their TCH and tried jimmy's test?

9. Does anyone have experience with an aftermarket block heater, or aftermarket engine heater of any kind installed in a TCH?

Thanks for any info.

Jack

 

I agree 100%. I could easily make it to my local convenience store and back without firing the ICE. Unfortunately, we do not have a factory installed EV only mode selector available to allow us to restrict the ICE for those short trips.

While we're discussing the pre-heat vs. engine running, I'd be curious about the math for the cost of running the electric heater for 2-3 hours to get the engine temp up vs. the cost of the fuel to run the engine for 1 or 2 miles in order to get to the same temp. Psychologically we feel the plug-in is better since we're not spending money for gas, but we DO still have to pay that electric bill and think about the potential emissions from the power source used to generate that electricity (coal vs. nuclear vs. oil vs solar vs. hydro).

 

There have been other threads on this in the past, right down to the part to order from Toyota (I believe it has to be ordered from a Canadian dealer). Someone performed an economic analysis, and it can save some money -- seems to me it saves about 2x in gas what it costs in electricity. I'd expect the savings would be greater the more trips you make from home on a cold (but heated) engine.

Of course the question is is the nuisance factor greater than the savings factor?

 

This is very rough, and perhaps with more data, and perhaps with some input from others, I will, later, be able to do better, but here we go:

My experience is that a comparison between fuel consumption over the first few miles, cold engine vs. warm, shows that it takes at least a differential of 0.2 gallons extra of gasoline to warm the TCH engine up. (Now that's in Houston during spring and early summer. In colder climates, I suppose it would take more fuel for the warm-up.)

Jimmy's experience is that it takes 2-3 hours at 300 - 350 watts to do the electrical warm-up to 125F. This is approx. 1.0 KW-hour. (Again, he's in a little colder climate, so I might get a higher temperature and/or need a shorter time.) I pay about 15 cents per KW-hour; so a daily warm-up would cost me me about $4.50 a month.

On the other side of the comparison, even if the electrical warm-up would save only half of the 0.2 gallon warm-up penalty, I could save 3 gallons a month. And, I usually use 15 gallons or less a month; so, I could see a 20% reduction in my fuel use. That would be enough to send my average mpg from the high 20's to the mid 30's (in SPITE of my typically short trips), and decrease my fuel bill by $12.00 a month, or over two and a half times the cost of the electricity.

The savings on those otherwise mostly EV-mode only trips to the convenience store would be even more impressive but the analysis is a little more difficult because of the deferred cost of the extra gasoline needed to recharge the battery later; so, I think I'll do that later.

As for the energy use and carbon impact, I think it's fair to say that the benefits would be, percentage-wise, greater than the fuel cost savings - because of the higher operating efficiency of electric power plants vs. automobiles (even the TCH). But that too I will leave 'till another day.