[AgentElrond]

My chosen route to/from work takes me through 2 residential areas (intentionally); mostly 25mph but one stretch is 30mph. I normally don't have any problem staying in "stealth" (battery only) the entire length (about 5 min. each).

In an effort to boost MPG, I've left the A/C off. As the weather's been getting warmer here (Central FL), the interior fan (on "auto") runs at a higher speed, as expected. Over the past 2 days, however, I've had a hard time staying in "stealth" mode; the battery has otherwise shown a "normal" (75-80%) charge level at the time.

As an "experiment" on the way home tonight, I shut off the fan altogether; also to help listen for when the gas engine started. From that point on, I had no trouble staying in "stealth" mode.

So... is this possibly related to the (electrical) energy required to run the interior fan on "high" constantly... or is it just me? :wink:

 

[windsurfdog]

As a fellow Floridian, my advice is to enjoy that wonderful A/C and let the hybrid system do what it does best. This car has the best A/C system I've ever owned, but that's not saying much considering it's the first automatic system I've had. I'm sure the only time I'll be turning the A/C compressor off is during the coolest of winter days. And I'm still averaging 49 mpg with A/C on 100%.

 

[Ray Moore]

My chosen route to/from work takes me through 2 residential areas (intentionally); mostly 25mph but one stretch is 30mph. I normally don't have any problem staying in "stealth" (battery only) the entire length (about 5 min. each).

In an effort to boost MPG, I've left the A/C off. As the weather's been getting warmer here (Central FL), the interior fan (on "auto") runs at a higher speed, as expected. Over the past 2 days, however, I've had a hard time staying in "stealth" mode; the battery has otherwise shown a "normal" (75-80%) charge level at the time.

As an "experiment" on the way home tonight, I shut off the fan altogether; also to help listen for when the gas engine started. From that point on, I had no trouble staying in "stealth" mode.
So... is this possibly related to the (electrical) energy required to run the interior fan on "high" constantly... or is it just me? :wink:

If you stop trying to stay in electric only and instead use the gas engine for accelleration and then coast without battery power when you can, you will see a big improvement in your overall gas mileage. The car is more efficient when the battery is not run down with the possible exception of an approach to a long downhill. After you stay in stealth for a period of time your battery will be at 4 bars or less. You will then be running the ice more until the battery is back up to around 6 bars. Even "no arrow" coasting is more difficult to attain with a depleted battery. All of this is due to the ineefficiency of converting kinetic energy to and from electric energy. If the conversion process were 100% efficient then there would be no penalty but alas it is not. There is no such thing as a free thermo-dynamic lunch. Oh, and go ahead and use the AC. If you employ the strategy that I am presenting, your mileage will increase more than the AC will cost you.

 

[AgentElrond]

Thanks for the advice; I'll try it.

 

[Gil Smith]

Typical charge indication

With 1200 miles now and (only) a 38 mpg average, with 55 on hiway, I note that I'm usually two bars down, occasionally three, and rarely 1.

Wonder whether this is far off normal.

 

[V8Cobrakid]

I normaly try to never use Stealth mode. If i do, it's a treat because i generated enough electricity that the ICE won't turn on by itself. Normaly i try to run only the ICE in a mode where it charges the battery and runs the wheels. When your battery gets fuller, it will turn on the electric engine which will skyrocket your mpg. Just make sure to get up to speed faily quickly. If you're accelerating slowly the entire way, you burn up more fuel.

I think running your electric motor by itself waist electricity. So, like i said: unless the synergy system forces me to use the electric motor, i try not to run in stealth mode. Unless i'm showing off... but that's a different story.

 

[BIF]

This is normal for mine.

I'm very rarely in the green zone (one bar down), and very rarely in the red zone (two bars remaining). Most often, I'm in the blue range.

 

[Gil Smith]

Battery charge state

I inquired through Toyota why I can never get a "full charge", and so maximize electric motor use. I was told that the computer circuit is set so that it is not possible to fully charge in order that the battery never be over-charged. Just wish the first 5 minutes made better use of that battery ! (23 mpg)

Agree that the steering, sadly, is too quick at highway speed to stay in the middle of the lane - especially in a cross wind or a passing semi. Maybe the next model...

A real neck twister to ID and change a fuse under the dash.

What a fantastic turning radius, music system, gas discharge headlights, seat comfort, etc., etc.

 

[RSnyder]

Re: Battery charge state

Just wish the first 5 minutes made better use of that battery ! (23 mpg)

That's exactly when it makes the most use of the battery. (Hence the 23 mpg).

The main goal is to minimize pollution. So until the catalytic converter has a chance to warm up, the engine runs with a light, steady load to heat up quickly. The battery takes care of moving the car during this time (up to the limits of it's power output). Once the engine is hot, it has to spend extra energy to recharge the battery. (Again, hence the 23 mpg).

I think Toyota intended to reduce the warm up time by using the thermos. From reports like yours, I get the feeling it's not as effective as they may have hoped.

 

[V8Cobrakid]

if i drive the way i've been practicing, i'll go for 13 miles in the morning to work and get around 60mpg. the rest of the day with the speeding traffic.. and stops is what kills my mpg. usualy my first 5 minute intervals are good 40+mpg. I wish there was a nice sicluded flat road wherever i was going.. then i should be able to pull a 65mpg average.

 

[bradca21]

I wish there was a nice sicluded flat road wherever i was going.. then i should be able to pull a 65mpg average.

Just have your commute go over the same roads and clearly DOWNWARD sloped hill that the EPA used to test the vehicle. I can guarantee your mileage will be around 51/60 :wink:

 

[snlcross]

Got mine up to 64+ last night. Keep your feet off the brakes, and don't pounce on the gas. drove about 35-40mph around town.

 

[Richard]

the rest of the day with the speeding traffic.. and stops is what kills my mpg.

Yeah, me too. Aren't these things supposed to get like 800 mpg in the city or something? I'm getting lower in the city than on the highway. Am I driving wrong? FIX IT FIX IT

 

[windsurfdog]

Richard said:

FIX IT FIX IT

Sounds like user error to me........If you are not pleased with your current mileage, buyers are stacked like cord wood for your car.........

 

[mdacmeis]

Re: Battery charge state

Just wish the first 5 minutes made better use of that battery ! (23 mpg)

That's exactly when it makes the most use of the battery. (Hence the 23 mpg).

Why do you say this? The reason for low mileage during the first five minutes is thermodynamics. The cylinder head is warmed by the stored coolant, however the remainder of the engine still must be warmed. This is simply the way a gasoline engine works.

The electric motor is no more in play during this warm-up cycle than any other. The gas engine responds to the load required. For many people, during the first 5 minutes they are backing out of a garage, driving down the driveway, and progressing to a main road. The gas engine is thus spending much of its time at low RPM while it is both providing power and warming itself up, which extends the warm-up time and reduces overall mileage. You can refer also to discussions about the different phases of operation, which require certain speeds to be attained and RPM checks in addition to temperature requirements before one can get into stealth, etc. But to say the electric motor is doing most of the work during warm-up and thus the cause of low initial mileage is wrong.

 

[RSnyder]

Re: Battery charge state

The electric motor is no more in play during this warm-up cycle than any other.

Maybe not it yours, but according to my miniscanner current reading, it certainly is in mine.

 

[Ray Moore]

Re: Battery charge state

Just wish the first 5 minutes made better use of that battery ! (23 mpg)

That's exactly when it makes the most use of the battery. (Hence the 23 mpg).

Why do you say this? The reason for low mileage during the first five minutes is thermodynamics. The cylinder head is warmed by the stored coolant, however the remainder of the engine still must be warmed. This is simply the way a gasoline engine works.

The electric motor is no more in play during this warm-up cycle than any other. The gas engine responds to the load required. For many people, during the first 5 minutes they are backing out of a garage, driving down the driveway, and progressing to a main road. The gas engine is thus spending much of its time at low RPM while it is both providing power and warming itself up, which extends the warm-up time and reduces overall mileage. You can refer also to discussions about the different phases of operation, which require certain speeds to be attained and RPM checks in addition to temperature requirements before one can get into stealth, etc. But to say the electric motor is doing most of the work during warm-up and thus the cause of low initial mileage is wrong.

Actually, based on my observations, the engine use is minimized in the first five minutes as much as possible and the ECU uses the electric motor as the primary driving force. If you try to accelerate at a rate that allows the engine to run and charge the battery you will find it almost impossible when the engine is cold. The engine will idle low and the battery will continue to drain as the electric motor supplements to drive the car. This is designed to reduce emissions during the initial warmup. IMO

Later, when the engine is warm it is very easy to accelerate at a rate that allows excess capacity to generate energy to store in the battery.

This warmup design based on low emissions is a major factor in the poor mileage at warmup. This occurs for about two minutes and the next three minutes are spent charging the battery from this rundown. Almost anytime you power the vehicle entirely with the battery you will lower your overall fuel efficiency due to the inherent losses in the conversion process.