[Trihard]

Hi,

I have noticed on my new hybrid limited (my first hybrid) that it will not go into EV mode upon starting her up for a few minutes (maybe 5?) despite the battery being full and going super easy on the gas. Is there a known warm-up time till it will engage? Is this the same for everyone? I haven't played around with putting it into the specific mode via the buttons...I'm just talking about standard driving in normal mode.

Thx.

 

[NewRavFan]

In the winter, you may find it hard to go into EV mode with a cold car depending on the outside temperature. Right now temps in Chicago are below 10F in the morning and my hybrid Rav refuses to use EV mode for the first 5-6 minutes until it warms up. On warmer days (temps in the 30's), it is much easier to get into EV mode.

BTW - if you try to force EV mode with the button the car will simply tell you EV mode is not available and return to the previous mode you were in.

 

[Robert831]

I had a Prius for 5 years, and it was the same way. EV mode is completely useless unless you have a plug-in hybrid.

 

[rdgrimes]

Hi,

I have noticed on my new hybrid limited (my first hybrid) that it will not go into EV mode upon starting her up for a few minutes (maybe 5?) despite the battery being full and going super easy on the gas. Is there a known warm-up time till it will engage? Is this the same for everyone? I haven't played around with putting it into the specific mode via the buttons...I'm just talking about standard driving in normal mode.

Thx.

Its complicated. Due to restrictions imposed for reasons of limiting emissions, the ICE must remain running till it reaches operating temps. There are actually 4 thermal stages for the system, and EV is only available in the last 2 stages. Stage 3, EV is available up to about 10mph, and only in stage 4 is it fully available. The manual details further restrictions.

 

[internalaudit]

And the sales manager tells me I wasted money on the block heater.

Even if it's not in full EV mode, the hybrid motor does kick in in a lot of situations to assist the gasoline engine, doesn't it?

 

[rdgrimes]

The block heaters are a Canada-only option. They make no difference in average MPG, they are intended mainly as a comfort feature - to give you heat quicker on a cold morning. OF course, in the arctic you need one to get the ICE to turn over at all.

Hybrid tech 101: Both ICE and electric are working all the time, except above 70mph and when in EV mode.

I forgot to add above: in winter the ICE will sometimes run solely to make heat in the cabin.

 

[Quickdtoo]

Toyota uses EHRS to use exhaust heat to warm coolant in the Prius and other Toyota based hybrids, I don't see the unit on the Rav4 hybrid tho.


http://energy.gov/sites/prod/files/2014/03/f8/deer11_barrieu.pdf


http://auto.howstuffworks.com/fuel-efficiency/hybrid-technology/exhaust-heat-recovery-recirculation.htm

 

[NewRavFan]

Yes - you can easily monitor that from either the main or 4.2" display

 

[rdgrimes]

Toyota uses EHRS to use exhaust heat to warm coolant in the Prius and other Toyota based hybrids, I don't see the unit on the Rav4 hybrid tho.


http://energy.gov/sites/prod/files/2014/03/f8/deer11_barrieu.pdf


Introduction to How Exhaust Heat Recovery and Recirculation Works - How Exhaust Heat Recovery and Recirculation Works | HowStuffWorks

They do everything they can to speed engine warming. If they didn't, the thing would never warm up. The Gen-4 2016 Prius is now using automatic radiator louvers too.

 

[Langutah]

Toyota uses EHRS to use exhaust heat to warm coolant in the Prius and other Toyota based hybrids, I don't see the unit on the Rav4 hybrid tho.


http://energy.gov/sites/prod/files/2014/03/f8/deer11_barrieu.pdf


Introduction to How Exhaust Heat Recovery and Recirculation Works - How Exhaust Heat Recovery and Recirculation Works | HowStuffWorks

Wow, great references @Quickdtoo. (from this hybrid newbie..)

 

[Trihard]

Thanks to everyone who has responded. I tried looking at both displays eco info from startup until the first time the EV light showed up and I couldn't tell any difference. From my newbie perspective, it looked like the car was operating under electric power way before the EV light showed. Does the EV light indicate more or less than what it appears based on the Eco monitors?

 

[internalaudit]

Its complicated. Due to restrictions imposed for reasons of limiting emissions, the ICE must remain running till it reaches operating temps. There are actually 4 thermal stages for the system, and EV is only available in the last 2 stages. Stage 3, EV is available up to about 10mph, and only in stage 4 is it fully available. The manual details further restrictions.

So if ICE reaches operating temps faster with a block heater, won't that allow for the ICE to shut off sooner? Oh well, I'm glad this winter has been mild.

The block heaters are a Canada-only option. They make no difference in average MPG, they are intended mainly as a comfort feature - to give you heat quicker on a cold morning. OF course, in the arctic you need one to get the ICE to turn over at all.

Hybrid tech 101: Both ICE and electric are working all the time, except above 70mph and when in EV mode.

I forgot to add above: in winter the ICE will sometimes run solely to make heat in the cabin.

 

[rdgrimes]

So if ICE reaches operating temps faster with a block heater, won't that allow for the ICE to shut off sooner? Oh well, I'm glad this winter has been mild.

You'd think so, but not really. In cold weather the system is immediately cooling down by itself, so the benefit from the block heater is gone in a couple minutes. It's nice to have a smidgen of heat right away though. The Prius block heater is only 400w, so its not like the block is toasty warm. I'm guessing its the same heater used here.

I have one in my Prius-v, it was a waste of money as far as saving gas goes, but on a cold morning its nice. To put it another way, it uses more energy than it saves.

 

[rdgrimes]

Thanks to everyone who has responded. I tried looking at both displays eco info from startup until the first time the EV light showed up and I couldn't tell any difference. From my newbie perspective, it looked like the car was operating under electric power way before the EV light showed. Does the EV light indicate more or less than what it appears based on the Eco monitors?

The EV light means the ICE is completely off.
You can still have the ICE running and not really burn any gas as long as your power gauge is below the 1/2 way mark. (EV zone) The ICE is just idling.
I'll suggest that you pay more attention to the road and less to the display! :wink

 

[Ravish]

In the winter, you may find it hard to go into EV mode with a cold car depending on the outside temperature. Right now temps in Chicago are below 10F in the morning and my hybrid Rav refuses to use EV mode for the first 5-6 minutes until it warms up. On warmer days (temps in the 30's), it is much easier to get into EV mode.

BTW - if you try to force EV mode with the button the car will simply tell you EV mode is not available and return to the previous mode you were in.

^This. I'm in Winnipeg and we've had some temperature fluctuations and I've noticed a big difference with the EV engaging. If I'm in the 0 to -10 celcius range, the battery charges and seems to hold the charge good so you do get to use EV faster. This week its dropped below -20 and it takes a while to get the EV activated. You still get the EV assist with the gas but it takes the vehicle a while to warm and as a result, longer for EV to become available.

Just as an example, my commute to work is 15-20mins. In the 0 to -10 range I'll get to use EV but below -20 its rare EV only will kick in (still get some assist). However, had to pick the wife up at the airport last night and after about 15mins into the commute the EV would cycle through and take over at times.

I'm thinking/hoping it will be much more active in the April to October months and curious to see the differences in fuel efficiency.

 

[turbotom]

Wow, those are some really cold temps. I will second the comment about turning the heat off. My car tends to keep the ICE on a lot longer if the heat is on. I keep telling myself its not worth being cold in my car with gas prices under $2 a gallon but I just can't help trying to get the highest MPG I can.

 

[rdgrimes]

^^^
There are many times when you can make the ICE turn off and on just by turning the HVAC off and on.

But the fact is that the amount of time the ICE is running isn't a huge factor in your MPG. If its just running to keep warm, its not using much fuel. Cold weather lowers MPG mainly because of the cold tires, cold chassis, cold air, etc. IOW - increased drag. You can generally expect anywhere from 10-20% improvement in MPG in warm weather. Best hybrid MPG here is when ambient temps are in the 70'-80'F range.

 

[internalaudit]

So if the a/c is off with fresh air coming in (applies more to highway driving than city as the exhaust fumes from the vehicles in front can still get in easily when driving at a much slower speed), wouldn't there be much less of a toll on fuel economy? It's the a/c that drives the compressor, doesn't it? The blower fan consumers very little energy, correct?

 

[rdgrimes]

The HVAC system has very little impact on MPG, except in those conditions where its running at or near full blast. Running the car in ECO mode lessens the impact of the HVAC on energy use.

 

[internalaudit]

The HVAC system has very little impact on MPG, except in those conditions where its running at or near full blast. Running the car in ECO mode lessens the impact of the HVAC on energy use.

By full blast, did you mean cooling? As I understand with heating, it's just coming from the engine/radiator heat.