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Hello all,
I've noticed that, as a rule, I can achieve slightly better mileage by driving myself vs. letting the cruise control adjust the throttle. Particularly where the speed limit is in the 40 to 45 mph, I can feather the throttle and get it into electric only mode (99.9 mpg), whereas the cruise control will seldom allow cruising in electric only mode, unless going dowhill or decelerating.
Any comments / other strategies employed?

ryecatcher

BTW, I AM obsessed by mpg on this car, and I'm not rehabbing. Never!
 

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Cruise will go EV on flat or slightly downhill roads, but it isn't interested in money so it kicks in the gas at its earliest convenience.

If Toyota was nice, there'd be an UltraGasMiser setting in the next software revision that would hold back a bit more on ICE useage. Although, what with their odd fear of excessive EV leaving us switchless, it's not likely...
 

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That may be the case in some instances, but I believe in the long run the car & its computers will make the best choices, and that any advantage would be either non-existent or miniscule.

Like many things in life, driving this car is more fun when you dont feel you have to "perform". :)
 

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I'm happy with 51.9 the cruise control gets on the interstate, why get upset trying to beat the computer?
(that's with suitcase, toolbox and 2 computers in the back)


2005, milennium silver, option 6 and 3900 miles on it.
 

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What speeds are you guys driving at to get 58 MPG on cruise control? I just drove 240 on NY interstate highway and ended with a 42MGP count. I was cruising around 80 MPH with cruise control... too fast?
 

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dbw784 said:
What speeds are you guys driving at to get 58 MPG on cruise control? I just drove 240 on NY interstate highway and ended with a 42MGP count. I was cruising around 80 MPH with cruise control... too fast?
For me to get 58-60 MPG would require a warmed up car plus no hills plus cruise control speed of 75-80 km/h (= 47-50 mph).
 

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I'm with dontcheff and I'll also add that I rarely get to drive in those conditions!
 

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Does driving in electric really improve MPG? Sure, while you are in EV you get infinite MPG, but that energy had to come from the gas engine, only now through inefficient conversion from gas to electric to battery to electric to kinetic.
 

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Depends, I would drive around my university in EV mode and wouldn't mind dropping a few bars cause I know I'll charge them back up on the highway out of the university. However, if it wasn't for the highway, I'd probably not be so eager to use it.

Simply stating, if you'll be travelling at a constant speed high enough for the engine to run later on, feel free to use EV mode since the engine's running, it'll send some charge to recharge the battery. If it's already full, then where's the extra energy gonna go? nowhere.
 

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KTPhil said:
Does driving in electric really improve MPG? Sure, while you are in EV you get infinite MPG, but that energy had to come from the gas engine, only now through inefficient conversion from gas to electric to battery to electric to kinetic.
From what I have seen on my Prius, using the EV switch does not improve the MPG. I use it now only when for about 200-500 meters after leaving the parking place and same distance upon arrival.
 

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Agreed, times near startup/shutoff can yield a gain. But you don't usually use cruise control for those times! The question was about using cruise vs. electric mode, and I still believe the mileage gains are an illusion. Sure, a five minute interval may show great mileage, but true MPG is not a function of time, but of miles and gallons. All that EV energy came from the ICE, which is a cruise control scenario involves driving many miles at a constant speed. Under those conditions, I would expect no real MPG gain, just a high 5-minute plot. What you won't notice on the graph is the resultant lower segment while it had to both charge the battery and propel the car, which will more than compensate.
 

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Here's a simple example... if you could get up a slight hill in EV mode and then regain the charge on the following downhill through regen alone, you'd do well.

So... the next generation should make use of 3D GPS and allow you to optionally specify a route, then have the computer take terrain into account...
 
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