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Seems a little low.

You would figure the engine wouldn't run so rich while cold (30 degrees F) - (more fuel = lower combustion temperatures). Only drive one or two miles in ERDTT (for about 5 minutes) but, what a hit to MPG.

I'm thinking the gas "guess-O-meter" may be off and needs to recalibrate.
 

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Seems a little low.

You would figure the engine wouldn't run so rich while cold (30 degrees F) - (more fuel = lower combustion temperatures). Only drive one or two miles in ERDTT (for about 5 minutes) but, what a hit to MPG.

I'm thinking the gas "guess-O-meter" may be off and needs to recalibrate.
Modern cars inject extra fuel to heat up the catalytic converter fast so it becomes functional. All ICE suck for the first 5-10 miles so I'm not at all surprised at that reading.

I've watched my Gen 1 tank down to 10mpg like it was pushed off a cliff, then work it's way back up to reasonable as the engine gets warm.
 

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Instant MPG is misleading for any vehicle. It could hit 99mpg if going downhill on most ICE cars.

For perspective: At full power, a 700HP Hellcat uses a tank of fuel in 20 minutes.
 

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If your driving slow that's what it is.
I've had it as low as 9 mpg.

Drive faster and your mpg will go up in the 20's

I would recommend a somms resistor.

I only need mine 2 months a year but well worth it.
 

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Unfortunately the estimate may be right. As pointed out, the engine needs to run to heat up the cat converter. So you pay a big price. In pollution as well by the way. A Prius would get about the same MPG. Sad fact of life. Wish ERDTT wasn't needed. On a trip it won't matter since you're covering a lot more ground and the engine is a lot more efficient.
 

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No that is pretty much standard. The gas and elec runtogether during erdtt though so your mpg will be 40-50 or 60 that depends.....I guess you could hold mode and go to all gas but then your overall mpg would be in the 30's
 

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Seems a little low.

You would figure the engine wouldn't run so rich while cold (30 degrees F) - (more fuel = lower combustion temperatures). Only drive one or two miles in ERDTT (for about 5 minutes) but, what a hit to MPG.

I'm thinking the gas "guess-O-meter" may be off and needs to recalibrate.
Not unexpected especially if some of the time the engine is running, you're stopped in traffic.

Also, you could always change the setting under Engine Assisted Heating in the Config menu to "Deferred" ... when this is done, ERDTT will only occur when colder than 15F, rather than the default 35F.
 

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How are you calculating the MPG?

In ERDTT mode energy is also put into the battery, so the only decent way to measure it is with a dead battery and end the drive with a dead battery.

If I look at the gas miles driven divided by the gas used I get meaningless results. In the single digit temps, fan only mode (no electric heat), and I calculate around 14 mpg on short trips, but also my electric range extends way out as the engine is running a lot more. However, if I factor in the extra electricity generated it is about 25 mpg.

My point is that if you calculate by EV miles and gas miles driven in the display, with ERDTT on you will see your electric driven efficiency go up and your gas efficiency go down. As I said, just don't charge your car one day and drive it around to see what kind of efficiency you are really getting. I think ERDTT will actually reduce your overall energy use assuming you would have used electric heat.
 
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