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Discussion Starter #1
OK. so I did a little experiment. I wanted to see what would happen if I unplugged the switch that tells the car that the hood is open or closed. It was easy to do, took all of 30 seconds. I wanted to see if I could get a faster 0-60 time by using hold mode and having the engine already running while sitting still.

Well, so here's the deal. Obviously the engine fires up as soon as you turn the car on. That's what I expected.

What I did not expect was that as soon as I put the car in drive and started moving, the engine turned back off. Then when I came to a stop, it would come back on. So I put the car in hold mode. This didn't force the engine on the whole time, but what it did do was allow me to take off from a dead stop with the engine running, and the engine continued to run during my acceleration test. The car DID feel faster on takeoff than it normally does in hold mode.

So, maybe this weekend I'll take the car to the drag strip and do an official test. My hope is the 0-60 time will actually be better than what I have gotten in the past in either normal or hold mode.

It did set the check-engine light, however. I hope it will turn itself back off after a few restarts of the car. I have a scantool, I just don't feel like digging it out since I know exactly what the cause is.
 

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Having the engine on or off makes no difference, the current to the motor is software limited and doesn't change if the motor is on or off. You may get different track numbers as any two runs are never the same.
 

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Discussion Starter #3
Having the engine on or off makes no difference, the current to the motor is software limited and doesn't change if the motor is on or off. You may get different track numbers as any two runs are never the same.
Actually, it makes a lot of difference. The car behaves differently in hold mode versus EV mode. This has been proven now, not only by me, but by others, scientifically. It is faster in EV mode in the low speeds, around takeoff. It is faster in hold mode at the higher speeds. So I'm hoping to get the best of both worlds by having the engine running at takeoff. I wouldn't be surprised if it shaved .5 seconds off of the 0-60 time.
 

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Ok, I'm confused, why does unplugging the hood latch switch make the engine run?
 

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Ok, I'm confused, why does unplugging the hood latch switch make the engine run?
Because the Volt has a "feature" where if he car is turned on then the engine starts running when you open the hood. It's to make it easy for a service tech to perform checks that require the engine to be running.
 

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It's some sort of mechanic's tool idea. And it's a way to hear what the engine sounds like if you are in the market for one.

But, alas, it's old school and smelly to have an flammable liquid burning thing in you car.

The Spark EV is much faster !!
 

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It's some sort of mechanic's tool idea. And it's a way to hear what the engine sounds like if you are in the market for one.

But, alas, it's old school and smelly to have an flammable liquid burning thing in you car.

The Spark EV is much faster !!
Did some looking at the spark -- much faster you say? it's 0-60 is listed at 7.9 seconds, ive seen numbers for the 2nd get from anywhere from 7.5 to 8.4

Maybe a tenth or two depending on which way the sun is facing and wind is blowing (joke) but I'd happily give up a tenth or two of speed so I woulnd't have to drive the ugly/tiny spark.
 

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Actually, it makes a lot of difference. The car behaves differently in hold mode versus EV mode. This has been proven now, not only by me, but by others, scientifically. It is faster in EV mode in the low speeds, around takeoff. It is faster in hold mode at the higher speeds. So I'm hoping to get the best of both worlds by having the engine running at takeoff. I wouldn't be surprised if it shaved .5 seconds off of the 0-60 time.
The two motors will only get so many kW to them, and that's regulated by the computer. You can max that kW number on pure battery alone. Why do you think you'll be able to push more kW into the motors with the gas engine running? No matter what propulsion mode you're in, it's not going to make the motors pull more kW.
 

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Because the Volt has a "feature" where if he car is turned on then the engine starts running when you open the hood. It's to make it easy for a service tech to perform checks that require the engine to be running.
It is also a safety feature to deter people from poking when the hood is up and having the engine kick on causing injury.
 

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Discussion Starter #10
The two motors will only get so many kW to them, and that's regulated by the computer. You can max that kW number on pure battery alone. Why do you think you'll be able to push more kW into the motors with the gas engine running? No matter what propulsion mode you're in, it's not going to make the motors pull more kW.
Because in hold mode, the engine will be directly driving the wheels, along with the motor(s). So nobody is saying that it is going to pull more than 120KW from a motor or battery.
 

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Because in hold mode, the engine will be directly driving the wheels,...
No, the direct coupling of the drive wheels happens only in a certain power and speed range, like highway cruising conditions.
As soon as you floor it in that condition there is a slight pause as that 3rd clutch disengages and your back to being a series hybrid, with a 150 HP EV motor driving the wheels.
 

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Discussion Starter #12
No, the direct coupling of the drive wheels happens only in a certain power and speed range, like highway cruising conditions.
As soon as you floor it in that condition there is a slight pause as that 3rd clutch disengages and your back to being a series hybrid, with a 150 HP EV motor driving the wheels.
That doesn't make any sense, and here's why. If the car can only deliver 120KW of power with BOTH motors working together, how would it deliver 120KW with a single motor? After all, if it is in series mode as you say, where is the extra power coming from? My conclusion is that the engine is directly powering the wheels. I remember the engineers talking about this on the 2nd gen Volt, saying how the engine powers the wheels in most circumstances on the new version. It's more similar to the Prius now.
 

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..on the 2nd gen Volt, saying how the engine powers the wheels in most circumstances on the new version. It's more similar to the Prius now.
Oh, this may be so. I don't know about the changes in the transaxle in the Gen 2. Never mind....
 

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The two motors will only get so many kW to them, and that's regulated by the computer. You can max that kW number on pure battery alone. Why do you think you'll be able to push more kW into the motors with the gas engine running? No matter what propulsion mode you're in, it's not going to make the motors pull more kW.
There is some confusion where the OP is talking about gen2 and most of us are thinking of gen1...

But still, I have noticed better sustained acceleration in gen1 in Hold mode... it feels like the battery fades quickly in pure EV mode if you floor it to get on the highway. In Hold mode, I feel less of this fade above 30-40mph or whatever. No idea if gen2 feels the same.
 

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In any case, please do take it to the track and let us know! And of course be sure to do multiple runs -- in normal mode, hold mode, and hold-with-hood-sensor-unplugged modes. I for one would be interested to see the results.
 

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Because in hold mode, the engine will be directly driving the wheels, along with the motor(s).
Wouldn't that imply a transmission, which the Volt does not have? Hold mode simply directs the software to switch to the gasoline-powered generator as soon as it deems it feasible (not instantaneously, when I'm in the middle of driving and switch to Hold mode).

Our Volts are, in a sense, mobile computers with wheels. ;)
 

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Wouldn't that imply a transmission, which the Volt does not have? Hold mode simply directs the software to switch to the gasoline-powered generator as soon as it deems it feasible (not instantaneously, when I'm in the middle of driving and switch to Hold mode).

Our Volts are, in a sense, mobile computers with wheels. ;)
Oh, and I just read the earlier post on the difference between Gen1 and Gen2 Volts. Being a Gen2 owner, I'm not familiar with Gen1 characteristics... Sorry 'bout that.
 
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