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      07-23-2008, 05:42 PM   #1
ferrari6891
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Shifting into neutral with DCT!!! help!!

Ok, so a lot of people have been telling me that shifting from gear to neutral(to coast down a hill and save some gas) is bad for the DCT tranny and it will cause damage.
Is this true?
Is it safe to switch from gear to neutral while driving?
should i avoid switching while driving?
help me out!!!!
thanks
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      07-28-2008, 12:34 PM   #2
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If the owners manual does not warn against it, I would venture to say it would be ok for the tranny. However, it seems rather pointless to do such a thing IMHO, plus, you loose a bit of "control" over the car with it in neutral. I wouldn't bother with it personally, but to each his own I guess.
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      07-28-2008, 03:10 PM   #3
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If you can't afford the gas, you bought the wrong car.
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      07-28-2008, 04:20 PM   #4
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you should definitely avoid doing this while driving. no offense, but this is just as stupid as when people with automatic transmissions shift their car into neutral when going down a hill or something. you will lose power (thus, traction) to the tires, and the gas that you save will be very very very very very negligible. gas is not that expensive that anyone should be doing this.
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      07-28-2008, 04:47 PM   #5
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Why would you do that?
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      07-28-2008, 05:57 PM   #6
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Quote:
Originally Posted by ss109 View Post
If you can't afford the gas, you bought the wrong car.

+1000000000000000000000

Same applies if you are a treehugger.
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      07-28-2008, 07:31 PM   #7
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jeremy clarkson actually said that leaving it in gear actually saves gas... since the momentum of the car is pulling on the engine instead of only using gas to maintain idle

plus NOT safe to drive in N
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      07-29-2008, 03:19 PM   #8
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oh thats cool
i mean i can afford the gas
i was just curious if what people said was true
anyways,
thanks guys
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      07-30-2008, 01:18 PM   #9
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Also, when you completely take your foot off the accelerator, the car is no longer spraying fuel into the engine. It has been this way on our ECU's since the e36 I think.
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      08-05-2008, 10:56 PM   #10
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I found this interesting. I drove the DCT the other day, very impressed, but when I was coming to a stop I did put it into neutral and the car either stalled or shut itself off. I spoke to someone who delivered one and it did the same thing. Is this normal or a fluke?
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      08-05-2008, 11:08 PM   #11
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From what I understand, the car is better off in gear than neutral when coasting. When in neutral, the engine has to keep fuel injection going to prevent stalling, but if the car is in gear coasting, the wheels and the drivetrain keep the pistons moving, and supposedly the car is smart enough to not bother with fuel ignition.

I dunno if it's correct, but it sounded plausible. Besides, it's better to have control over your car for that 1 in a million time you need it.
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      08-05-2008, 11:18 PM   #12
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Quote:
Originally Posted by BMW1986 View Post
I found this interesting. I drove the DCT the other day, very impressed, but when I was coming to a stop I did put it into neutral and the car either stalled or shut itself off. I spoke to someone who delivered one and it did the same thing. Is this normal or a fluke?
Fluke...with DCT you can to neutral from any gear at any speed. The engine should not shut off.
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      08-05-2008, 11:24 PM   #13
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Quote:
Originally Posted by ss109 View Post
Also, when you completely take your foot off the accelerator, the car is no longer spraying fuel into the engine. It has been this way on our ECU's since the e36 I think.
What?
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      08-06-2008, 05:08 PM   #14
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Quote:
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Also, when you completely take your foot off the accelerator, the car is no longer spraying fuel into the engine. It has been this way on our ECU's since the e36 I think.
Huh? That doesnt make sense to me. If you are on a completely plane surface, and your car is in gear, and you let of the brake w/o apllying the gas, the car will go. You could do this for miles right. But you are using gas. You are using gas when your car is in nuetral and idling.
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      08-06-2008, 05:39 PM   #15
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Quote:
Originally Posted by Blip Bavarian View Post
Huh? That doesnt make sense to me. If you are on a completely plane surface, and your car is in gear, and you let of the brake w/o apllying the gas, the car will go. You could do this for miles right. But you are using gas. You are using gas when your car is in nuetral and idling.
I have to huh your huh.

1. What is a plane surface? Is that like a wing or fuselage or something?

2. What is letting of the brake? If you mean letting off the brake, the car will not go with 6MT or DCT, nothing happens on a flat surface, you will remain stationary

What this thread is referring to is when you are coasting to a stop or just slowing down with the car in gear, if your foot is not on the gas the engine shuts off the fuel to the engine, therefore you are not using any fuel at all. If you are slowing down and you put your car in neutral then the car must use gas to keep the car running at idle, thus using more fuel than if you leave it in gear.
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Last edited by skierman64; 08-06-2008 at 10:12 PM.
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      08-06-2008, 05:40 PM   #16
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being in neutral actually costs u more. while engaged in gear ur wheels spinning will keep the engine alive, otherwise the engine will need gas injected to stay alive
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      10-09-2008, 01:28 PM   #17
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awesome thread haha
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      10-09-2008, 01:39 PM   #18
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i know someone who failed a driving test because he was coasting and put it in nuetral
the tester said if you suddenly needed to accelerate, you would have to engage a gear first then accelerate
the time spent doing that could cause you to have an accident
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      10-09-2008, 06:23 PM   #19
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Well I sometimes shift to N sometimes when I am coasting to a driveway packed with people, rev my car up to 8000rpm and scare some kids. Of course after that, I will shift back to 1st gear and drive off. hehee...
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      10-09-2008, 10:23 PM   #20
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It's correct. If you're coasting down a hill in gear you will use less gas than if you were in neutral because the engine is just windmilling and no fuel is being injected until you depress the accelerator.
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