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Has anyone ever tried this approach to avoiding ERDTT situations? If there is no gas in the tank, will the car simply cease to function, or is this a way of effectively forcing the car not to start the engine at ~15 degree temperatures?
 

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Interesting idea. Not sure.

Not so interesting, potentially burning out the dry, air sucking fuel pump.
 

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Page 183 of my online manual (bold added by me):

If the vehicle runs out of fuel, ... (t)he vehicle will have less
responsive acceleration. DIC messages indicate reduced
propulsion power
, that the engine is not available, and the need for fuel
or service.
 

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Not worth it. You'll be stuck in PPR and possibly damage the engine/fuel system components by running it dry (I don't think it actually runs dry, there's always a slight reserve - but in winter that would make it prone to water accumulation and freezing can damage components). It also won't be able to run EMM.
If you don't want ERDTT, buy the prebuilt switch, or make your own resistor mod. Then your car can actually function otherwise normally while the engine sleeps.
 

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Has anyone ever tried this approach to avoiding ERDTT situations? If there is no gas in the tank, will the car simply cease to function, or is this a way of effectively forcing the car not to start the engine at ~15 degree temperatures?
You don't state your driving habits but Gen I in a very cold and long Michigan winter and driving a 1200 miles month I burned maybe 2 tanks of gas with ERDTT. $50 isn't worth the trouble of trying to outsmart the engineers IMO.
 

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The heating system needs help from the engine heating up coolant when extremely cold. It's only a few dimes worth of gas. Also lack of use is going to hurt that engine, then when you need it some situation is going to arise. In Alaska extreme cold I'd want to run it up to temp frequently.
 

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If you are trying to avoid using gasoline, you could walk, ride a bike, ride a horse, use public transportation, stay in bed, etc. I'm amazed at how many people knowingly pay so much money for a vehicle that runs on both electricity and gasoline and then do everything they can to limit themselves to the 40 - 50 miles on electricity. Why not spend you money on a Leaf that will go twice as far on electricity and use no gasoline at all?

VIN # B0985
 

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Regarding what happens with no gas in the tank of a Gen 1 Volt:

Our friend Ari Colin and I have both ended an FMM in our 2012 Volts by running the ICE until the tank is empty and the ICE stops. He does it while parked, to avoid registering any gas miles; I’ve done it while underway. You can’t drive on battery power while the FMM is in progress (forces you to use the old gas), even if it’s fully charged. Once the tank is empty, you regain access to the battery, but in Reduced Propulsion mode, allowing you to drive to a gas pump to get some fresh gas.

There’s a minimum amount you must add to an empty tank to bring an end to the FMM/Reduced Propulsion mode (~1.5 gallons). After you refuel and start the car, the ICE will run briefly to perform a self test, and once the engine starts successfully, will turn itself off and return you to normal operations, allowing you to continue in Electric or Extended Range mode (as described in the manual under the heading, Out of Fuel).

After you run the ICE until it stops itself because you’re "out of gas," a small amount remains in the system. If you fill your Gen 1 tank after running out of gas, as I do in my 2012 Volt, your next FMM will occur ~363 days later. Ari puts into his emptied tank only the bare minimum needed to end the FMM, and his next FMMs tend to be ~318 days later. The difference seems to be because the small amount of "old" gas remaining in the system lowers the "average age" of 1.5 gallons by a few days more than it does the average age of a full tank. Gen 2 gas tanks have a slightly smaller capacity (8.9 vs 9.3 gal), so the effect of residual gas on FMM cycles may vary.

You can also "run out of gas" by driving until your gas gauge reads empty. I drove until the Torque Pro app was reporting "0.0 gals gas / 0.0% tank volume" as I was parked on level ground near the gas pump. The ICE continued to run as I drove the very short distance to the pump, and after adding gas, the engine made no self test upon starting the car. Clearly, the system is not "Out of Fuel" empty when the OBD port first reports the car is out of gas, and, apparently, some gas still remains in the system even after the ICE stops running because the tank is empty.
 

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Discussion Starter #10
If you are trying to avoid using gasoline, you could walk, ride a bike, ride a horse, use public transportation, stay in bed, etc. I'm amazed at how many people knowingly pay so much money for a vehicle that runs on both electricity and gasoline and then do everything they can to limit themselves to the 40 - 50 miles on electricity. Why not spend you money on a Leaf that will go twice as far on electricity and use no gasoline at all?

VIN # B0985
Yikes, I'd just like to avoid ERDTT on my roughly 25 mile round trip commute. This drive can be accomplished entirely on battery power even with the heater on full blast in the winter, if it weren't for a few low spots in town that I pass through with temperatures in the low teens in the morning. ERDTT activates in these areas, even though the vehicle is already warm. The Nissan Leaf really isn't practical up here because of a complete lack of charging station infrastructure outside Anchorage.
 

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Yikes, I'd just like to avoid ERDTT on my roughly 25 mile round trip commute. This drive can be accomplished entirely on battery power even with the heater on full blast in the winter, if it weren't for a few low spots in town that I pass through with temperatures in the low teens in the morning. ERDTT activates in these areas, even though the vehicle is already warm. The Nissan Leaf really isn't practical up here because of a complete lack of charging station infrastructure outside Anchorage.
So what you are saying is that you don't want to accept any benefit from ERDTT for yourself and/or the vehicle systems. The designers of the Volt included things like ERDTT to allow the vehicle to operate more efficiently in places like Alaska. Living in Arizona I experience (and fully accept) the opposite of ERDTT when the A/C runs at times, even though I don't ask for cooling in the cabin. It does this to benefit the longevity of the HV battery which I will ultimately appreciate.

VIN # B0985
 

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So what you are saying is that you don't want to accept any benefit from ERDTT for yourself and/or the vehicle systems. The designers of the Volt included things like ERDTT to allow the vehicle to operate more efficiently in places like Alaska. Living in Arizona I experience (and fully accept) the opposite of ERDTT when the A/C runs at times, even though I don't ask for cooling in the cabin. It does this to benefit the longevity of the HV battery which I will ultimately appreciate.

VIN # B0985
Unlike your A/C which is required in order to keep the HV battery cooled, ERDTT is ONLY required for creature comfort NOT for any vehicle systems. Rollin' into my 5th consecutive winter with ERDTT 'fixed' and haven't run into any situation where I actually required this unnecessary fuel-wasting 'feature' on my Gen1!:p
 

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For all the folks who want to avoid erdtt, I'm one who likes to set erdtt to the higher temp setting in the name of overall range. I originally set it to the lower setting thinking that avoiding the engine would save me in overall MPG, but through multiple experiments during snowageddon 1 and 2, it turns out that I get better mileage in extreme cold by avoiding the resistive heat and using the ICE to heat the car during my commute. I would start the day doing a remote start early enough so that the car is fully charged before I need to depart. I would immediately use hold mode to get the engine warm and drive the interstate portion of my commute under ICE. When I hit city traffic I would switch to normal, but with the high erdtt setting to let the car generate heat when it needed it. There were times where I would hit city traffic showing maybe 35 miles of range and be able to drive 5-7 miles without losing a mile on the guessometer in the winter.

On the return trip home, depending on what the guessometer said, I would use hold mode again to get the engine warm so cabin heat is mostly from the engine and not resistive heat, then deplete the the battery still allowing erdtt at the high setting. But if the guessometer told me I had say 35 miles of battery life left, I would avoid the hold mode engine warm up and just drain the battery allowing resistive heat. My commute was 50 miles (now 65 miles) round trip with no charging at work, so I am guaranteed to always hit the Dino juice in the winter.
 

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Unlike your A/C which is required in order to keep the HV battery cooled, ERDTT is ONLY required for creature comfort NOT for any vehicle systems. Rollin' into my 5th consecutive winter with ERDTT 'fixed' and haven't run into any situation where I actually required this unnecessary fuel-wasting 'feature' on my Gen1!:p
Calling it "fuel-wasting" would be accurate if there was no benefit from the energy being consumed. But the designers use it to make the cabin comfortable with the most energy efficient system. It is also a source of energy that can be used for keeping the windows defogged, nothing says safety like being able to see where you are going. Working at the Milford PG and living in Michigan for 18+ years taught me that lesson.

VIN # B0985
 

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It seems to kick in based on ambient temperature, usually 14-16 degrees. My Gen 1 model was the same.

Which means as soon as I pull out of my garage and the low temp is detected the engine kicks on ?

So on days where the temp is always below -10C, which is most of Januarya nd February here, is there any point bringing the Volt in the garage to charge it? It's going to use the ICE anyway, so might as well save some electricity
 

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Calling it "fuel-wasting" would be accurate if there was no benefit from the energy being consumed. But the designers use it to make the cabin comfortable with the most energy efficient system. It is also a source of energy that can be used for keeping the windows defogged, nothing says safety like being able to see where you are going. Working at the Milford PG and living in Michigan for 18+ years taught me that lesson.

VIN # B0985
When I can pull out of my warm garage in my Gen1 with all windows frost-free just to go across town and less than a mile into this short trip the silly ambient temp sensor happens to drop just below the arbitrary trip point causing ERDTT to engage right as I am about to arrive even though the cabin is still quite warm then YES this is an unnecessary and complete waste of fuel IMHO!:rolleyes:
 

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Has anyone ever tried this approach to avoiding ERDTT situations? If there is no gas in the tank, will the car simply cease to function, or is this a way of effectively forcing the car not to start the engine at ~15 degree temperatures?
Why would you want to bypass this function. It's there for a reason. Why not just buy a pure-EV?
 
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