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After reading a member's post last month claming that sport mode saves more gas, I tried that out for a month and got an answer.

I live in Toronto and we have no hill here:D. Everyday, I cover around 103km (99km highway, 4km local). In the morning, I drive at 70km/h on 2km local road, then 40km/h to 60km/h on 22km highway (due to traffic jam:mad:), and 120km/h for the rest 27.5km highway. In the evening, traffic is pretty much different everyday... but the fuel consumption is not so much different than in the morning.

Previously, my driving habit was 90% eco, 8% normal and 2% sport. My fuel consmption was 4.7L/100km to 4.9L/100km.

After trying out the sport mode theory, I started use normal mode on local, and sport mode on highway. My fuel consmption drops down to 4.4 ~ 4.5. Although there is not a huge difference from before, but it still saves me a bit more gas;). And plus I can actually enjoy driving my car now, no longer need to stuck in eco mode to try to "save" some gas.

My non-educated thoery for sport mode saves more fuel is because of the acceleration part. When we accelerate in sport mode, the fuel consmption would go higher than accelerating in eco/normal mode, but at the same time, we are using less time and less distance to get the speed up to where we want it to be. The fuel consmption would then go down and uses the same amount of fuel as eco/normal mode as we hold the speed.

For example, if I drive in sport mode and accelerating, fuel consmption is 15L/100km, and takes me 1km to accelerate to the speed that I want, during this acceleration, I used 0.15L of fuel:

15 * 1 / 100 = 0.15L

If I drive in eco/normal modeand accelerating, fuel consmption is only 11L/100km, and takes me 1.5km to accelerate to the speed that I want. During this acceleration, I used 0.165L of fuel:

11 * 1.5 / 100 = 0.165L

However, sport mode may not save fuel sometimes. I made the following discovery:
1. Do not use sport mode on local road because before you finish accelerating, there's always a red light waiting for you ahead;).
2. Do not use sport mode if the traffic condiction does not allow you to go over 50 ~ 60km/h. That is because sport mode allows the gas engine kicks in much earlier than eco/normal. And you dont need this extra acceleration power when you are only going at 50, so you should stay in eco mode and take the advantage of the free electric power.
3. If you are not in rush, try not to go over 120km/h.
4. In sport mode, just drive normally, dont be too gentle during acceleration or else you are wasting more gas than eco/normal mode. I keep the RPM at around 2200 to 2800 during acceleration.
5. Dont floor the gas paddle.

I think that's pretty much it on my discovery. Enjoy your CT!!
 

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That is very interesting information and makes sense. I think in March/April people were posting that you got better mileage in normal vs. eco (for the same reasons you mention: the gas motor is on longer as it takes longer to get up to speed in eco mode) so I never use eco anymore but I never thought about sport being even better(getting to speed quicker - less gas used). I wonder too that because sport outputs more volts (which means more torque from the electric motor) you are getting up to speed even quicker - or using even less gas as there is more coming out of the electric motor?
Of course like you mention there are many other variables that affect mpg's a huge one being the conditions you are driving in so what works for one person may not work for another (like in the case of the guys who have to drive in and around the LA region).
 

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Well, I thought we were supposed to be using something like 75% throttle to get up to 'cruising velocity', then feather the throttle and use as little as possible to maintain the desired speed.

Which means we've still got 25% throttle left on the table with either Eco or Normal modes, and I don't think Sport pushes us to 125%?

I'll be the first one willing to go out and try Sport mode all day! I've been leaving it in eco 95% of the time! =]

And of course I'm totally new at this, I'm sure there's a guide online to maximizing mileage with a CT (or Prius), I just need to search for it and grok it.

That is very interesting information and makes sense. I think in March/April people were posting that you got better mileage in normal vs. eco (for the same reasons you mention: the gas motor is on longer as it takes longer to get up to speed in eco mode) so I never use eco anymore but I never thought about sport being even better(getting to speed quicker - less gas used). I wonder too that because sport outputs more volts (which means more torque from the electric motor) you are getting up to speed even quicker - or using even less gas as there is more coming out of the electric motor?
Of course like you mention there are many other variables that affect mpg's a huge one being the conditions you are driving in so what works for one person may not work for another (like in the case of the guys who have to drive in and around the LA region).
 

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I just started testing Normal mode instead of Eco mode and it does seem like Normal gets better mileage in city driving. I suspect that it's a result of hitting speed sooner and engaging the electric sooner but I don't care, I'm happy to have more throttle. I'll test sport mode next.
 

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Something is definitely strange. With my last tank of gas, I was mostly in Normal mode with about 30% in Eco mode, I was getting better mileage than the current tank of gas which is 100% in Eco mode. I am going to test Sport Mode with my next tank of gas.
 

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Don't forget that when in sport mode you get extra power out of the electric engine 650 V. Normal and eco-mode allows for 500 V.
 

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Like the other commentors on this thread, i have learned that driving in sport mode gives better milage. We drive around the SoCal area in all types of traffic, sport mode gives us an extra 2 to 3 mpgs. On a recent trip to Sacramento, e also discovered that driving with cruise control kills your gas mileage, the average for the 1100 mile round trip was only 40.2, considerably less than the 45+ mpg we normally get.
 

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I've found that cruise control in ECO mode on the highway gives the best mileage for highway driving, while cruise control in normal mode decreases mileage. Normal mode in city driving gives better mileage than ECO. I'm eager to start testing sport mode in the city. I can tell you this, when using sport mode to merge onto the freeway from an on ramp, it visually decreases the gas mileage on the meter, but given that Normal has given better city performance, I'd be thrilled if Sport added further improvement. I've already dumped using ECO mode around town - and I say good riddance.
 

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very interesting mr. original thread poster.

I also live in the Greater Toronto Area. I am getting similar fuel efficiency numbers.

I'm going to try this "Sport mode" on hwy.

My feeling is the additional 150V helps.
 

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I feel quite enlightened by this conversation.

I always thought that I was going to be able to maximize my consumption by leaving the car in ECO mode. Mind you if I was needing accelerate up a hill I'd flick it to SPORTS mode and then revert back to ECO mode.

Maybe I should now be leaving it in NORMAL mode for suburban travel and as a previous poster has suggested that when travelling on a highway at 110km per hour use ECO mode combined with cruise control.
 

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Had a decent trip to do with work today and ended up testing out the Sport vs Normal thing ... I usually drive on 40mph max roads, so I keep to Normal mode to make the steering easier on my arms. I'd concur with the "Do not use sport mode if the traffic condiction does not allow you to go over 50 ~ 60km/h." At low speeds Sport holds on to the engine for a while longer than necessary, which loses you mpg for no real benefit.

Normal vs Sport on motorway (70mph roads) :

When I'm choosing cars, I look for what I call "lean-on power". I lean slightly on the throttle and see what happens. I like to have enough reserve power available to allow me to do say 40-60 or 50-70 without changing gear or flooring it.

Normal doesn't really have that Lean-On power but Sport definitely does. The gearbox is slightly more responsive, especially when combined with the different throttle pedal -> throttle input profile.

Motor power - 650V is available for Normal and Eco at full throttle (there's a Lexus sales person trainer video somewhere) but the limit is usually 500V. Sport gets 650V available for all throttle pedal positions. Helps that "Lean-On Power" thing. That should mean more flexibility when you want to adjust the throttle slightly to keep the same speed on gradients.

I started the trip in Normal today but went back to struggling to maintain the consistent 70mph. That's the old Lean-On Power thing again ... I found it much easier to keep the consistent 70mph when switching to Sport. It's the changes of speed (kinetic energy equation) that'll murder the mpg. So because Sport was letting me keep to the consistent speed more easily, the mpg was happily going up more quickly.

Rpms ...

It's a bit like having an 8th or 9th gear :) 70mph in 6th in my Focus would need about 3200rpm. In the CT, a 70mph cruise today was going down to 2000rpm. 50mph (roadworks = boring) was taking it down to about 1100-1200rpm. That's incredible for a petrol car (fair enough for a diesel). This is where the CVT gearbox scores for us, it'll go to a silly high ratio for cruise but keeps the capability of a light kickdown when gradients come along. The engine is also supported by the massive torque from the motor which will come in before the engine spins up to a more power friendly rpm.

Urm - Wall of Text detected. I had a feeling that would happen ...

Normal - tougher to keep consistent speed so you lose mpg from booting it.
Sport - more Lean-On power lets you have more fun

I'll keep to Normal for town but go for Sport on the motorway trips. I have the feeling that Normal may actually encourage more heavyfooted driving because of the different throttle profiles. The hybrid ecometer is also not really useful outside of town (to judge the motor only point) so it's better to have more responsiveness.

Right now I'm enjoying having a responsive car that also combines great handling with toys and comfort. MPG is already the highest of any car I've owned, if I get to 50(UK) in the summer that'll be a big bonus :rolleyes:.

PS Apologies for this not being exactly coherent, I was just kinda working through the logic :D
 

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Well I tried the sport mode theory today. On my regular round trip commute of 64 miles I generally get between 52 to 54 mpg (uk gallons) in normal mode.Have measured this a number of times. In sport mode today I got 49 mpg. Mind you in sport mode you feel like you want drive faster but generally I think I maintained the same driving style.

Driving in sport mode is more fun so maybe now and then i will sacrifice the mpg.
 

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Sports cuts out the battery if going over 27mph.
I only do city driving. I accelerate using sports, go up hill using sport, cruise in Eco (can go as high as 40mph), go downhill using Eco and avoid braking as much as possible.
 

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For me, 110 miles roundtrip commute with mostly freeway driving.

Eco Mode: 49.2 mpg (over a full tank)
Normal Mode: 50.9 mpg (over a full tank)
Sport Mode: 44.5 mpg (130 miles into the tank so far)

These were car computer readings. My calculated MPG is a couple mpg lower than the computer reading in each case. There seem to be not much difference between Eco and normal mode, but I can definitely see a drop in MPG for sport mode. But the driving also feel a lot different. I think I might just keep it in sport mode if it does not drop any lower when I am done with this tank of gas.

Update:
Sport Mode: 46.8 mpg (185 miles into the tank)
Update 2:
Sport Mode: 46.9 mpg (over a full tank)

So the difference between Sport Mode and Eco Mode is about $3 per fill up. I think I will stay at Sport Mode. I only wish there is a way to start up at Sport Mode and not have to change it every time.
 

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I know that anecdotal "findings" are not all that reliable because of all the variables, but I just don't see how the sport mode could possibly be more economical that the eco setting. As I understand it, the eco mode also limits the A/C draw on the battery, which limits the need to recharge. The sport mode also produces slightly more battery power for better performance.

I don't know how more power can be produced for free. It has to come from somewhere. Pay me now or pay me later.
 

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First time on this forum. I bought my car in Sep. I have been using eco mode exclusively since that is what I thought I was supposed to do (although that will change after reading these posts). My first tank of gas was 41.2 mpg. After that it has ranged from 36 to 40 mpg. I have been very disappointed and therefore trying to limit my accelerations, etc. Since I'm doing mostly city driving, I will try normal mode and even sport mode when accelerating and see what happens. Any other suggestions to save gas?
 

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First time on this forum. I bought my car in Sep. I have been using eco mode exclusively since that is what I thought I was supposed to do (although that will change after reading these posts). My first tank of gas was 41.2 mpg. After that it has ranged from 36 to 40 mpg. I have been very disappointed and therefore trying to limit my accelerations, etc. Since I'm doing mostly city driving, I will try normal mode and even sport mode when accelerating and see what happens. Any other suggestions to save gas?
I like driving in Sport mode too (once the car warms up a bit), unless the weather is bad. I guess the best suggestion I have for better gas mileage is to try to get the car into EV mode as much as possible. I accelerate quickly and let off the gas to cruize in EV mdoe for as long as possible, then quickly increase speed and let off again. This technique has been discussed here many times and is know as 'pulse and glide'.
 

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I like driving in Sport mode too (once the car warms up a bit), unless the weather is bad. I guess the best suggestion I have for better gas mileage is to try to get the car into EV mode as much as possible. I accelerate quickly and let off the gas to cruize in EV mdoe for as long as possible, then quickly increase speed and let off again. This technique has been discussed here many times and is know as 'pulse and glide'.
Interesting... never heard of this 'pulse and glide' thing, but that's exactly how I had been driving! I was doing it because the manual said to break in the car, I should not drive at a constant speed for long period of time. So what I had been doing was varying between 60 mph and 75 mph on my 110 miles commute.
 

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I know that anecdotal "findings" are not all that reliable because of all the variables, but I just don't see how the sport mode could possibly be more economical that the eco setting. As I understand it, the eco mode also limits the A/C draw on the battery, which limits the need to recharge. The sport mode also produces slightly more battery power for better performance.

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I don't know how more power can be produced for free. It has to come from somewhere. Pay me now or pay me later.
It takes the same amount of energy to move the car from 0-40 whether in sports or eco. How much fuel is expended depends on how much the battery was used. Using sports, getting to 40 quickly and then cruising while hardly touching the gas may be just as economical. More so if Eco means going so slowly that you catch a red light and have to slow down/ stop
 

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It takes the same amount of energy to move the car from 0-40 whether in sports or eco. How much fuel is expended depends on how much the battery was used. Using sports, getting to 40 quickly and then cruising while hardly touching the gas may be just as economical. More so if Eco means going so slowly that you catch a red light and have to slow down/ stop
So you are saying that if I go from 0-40 in two seconds flat, I am using the same amount of energy as if I take two minutes? I am not a scientist and have never played one either, but from personal experience with gasoline powered vehicles, if I punched it to accelerate rapidly I could almost see the fuel gauge dropping. You are probably right, but it makes no sense so I am going to have to (reluctantly) do some research on this. No, I changed my mind. I will just say that something this counter intuitive will remain a theory until someone shows me some scientific proof, like a real world test under controlled circumstances.
 
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