GolfGTIforum.co.uk
Model specific boards => Golf mk5 => Topic started by: TeddyKGB on 31 January 2007, 20:30
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Hi!
When I've driven automatics in the past, when the car is stopped and you're in "drive" you can feel that the clutch disengages, or it doesn't bite or whatever until you take your foot off the brake.
OK, so the DSG isnt strictly automatic but in my golf when I come to a stop at lights, I notice that the clutch doesnt seem to disengage, ie I can still feel it biting and it wanting to keep moving so I put it into N when stopped. Is this right? Surely the clutch plate rubbing when stationary is bad practice even in a manual! :grin:
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If Im right, and Im no expert on Auto's, but when you apply brake in drive, you obviously stop and when you pull away all is Ok. Same with DSG.
Obviously you cannot apply the handbrake whilst in drive so when you stop at lights or junction, either apply the brake and thats all, leaving it in drive, or if you want the handbrake on, put it in park or neutral!
Im not quite sure what your asking?
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Ok, done some quick research:
Today DSG uses two wet multiplate clutches to connect to the engine, that can partially disengage on stop, to replicate the behavior of a torque converter, that is allowing the engine to idle while the car is stopped without putting the car in neutral (DSG still has the “forward creep†at stop of an automatic gearbox).
Help??
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Yes - I apply the brake in drive and keep it applied to stay stopped. But when stationary, the engine seems to "labour" because it seems to me and feels like the clutch remains slightly engaged and stays this way even though it's at a full stop.
Now normally when I've driven other auto's in the past, when you come to a complete stop in drive with the foot brake engaged, you hear a slight "clunk" as the clutch disengages. When you release the footbrake the clutch comes back in and the car gently moves off on it's own
Hope this makes more sense :smiley:
**edit** just seen your second reply - thanks, That makes sense I guess. Just worried incase it was causing damage
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Hope this helps - if you are still unsure this is correct, waz the car down to a car stealer get them to check it
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Not sure what other automatics you have driven but what you are describing is not right.
Auto's use a torque converter, there is no friction plates like a clutch so no need for anything to dissengage.
Try this link for a better undersanding: http://auto.howstuffworks.com/torque-converter.htm (http://auto.howstuffworks.com/torque-converter.htm)
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cheers acwats - that explains stuff better for noobs like me :grin:
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Not sure what other automatics you have driven but what you are describing is not right.
Auto's use a torque converter, there is no friction plates like a clutch so no need for anything to dissengage.
Not quite right.
The DSG is NOT a conventional automatic transmission. Auto transmissions have a gearbox containing epicyclic gears controlled by hydraulic brake bands, and a fluid flywheel, usually in the form of a torque converter.
The DSG 'box is actually a computer controlled "dual" manual transmission. This consists of two manual type mechanical gearboxes, and two multi-plate wet clutch packs.
The "D" mode, stationary effect is very different to a conventional auto, in that an actual gear ratio (1st) is actually engaged, and the corresponding clutch pack is held just off the bite point. The information supply controlling the 'box ECU comes from the wheel speed sensors (no signal at rest), and the brake pedal switch. When you release the brake pedal, the clutch is released more (but not fully) to an increased bite point, the car moves forward, and when the wheel speed sensors match pre-determined values, the clutch is fully released and full drive is transmitted from engine to gearbox.
HTH
Rgds
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See, how did i know you could come up with a text book answer! - i just took my quote from a search i did. Good job we got people like you on here!
Well done
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The "D" mode, stationary effect is very different to a conventional auto, in that an actual gear ratio (1st) is actually engaged, and the corresponding clutch pack is held just off the bite point.
Yes but isn't that "rubbing" (however lightly) a bad thing? Is it good practice to put it in N when waiting at lights? It would be a lot easier if you could shift it in and out of "N" with the paddles
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See, how did i know you could come up with a text book answer! - i just took my quote from a search i did. Good job we got people like you on here!
Well done
Sorry Lee, I wasn't having a go at you!!! It was acwats who posted the torque converter link, but the DSG box doesn't have one! :wink: :nerd:
Rgds
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The "D" mode, stationary effect is very different to a conventional auto, in that an actual gear ratio (1st) is actually engaged, and the corresponding clutch pack is held just off the bite point.
Yes but isn't that "rubbing" (however lightly) a bad thing? Is it good practice to put it in N when waiting at lights? It would be a lot easier if you could shift it in and out of "N" with the paddles
Not really. The box and clutch packs are working as they were designed. The clutch packs are actually immersed in oil, just like most motorcycles (except Ducati), and the oil carries away any heat build-up.
If you know the lights are going to be a long while on red, then of course it would make sense to apply the handbrake and put it in "N". You'll stop dazzling anyone behind with your brake lights too!
The paddle shift into neutral is not a good idea, because you need the interlock (foot on the brake) to stop you going into reverse accidently.
People really shouldn't call the DSG an "auto" - OK, it does have an automatic "mode", but the difference in it's design and construction between it and conventional auto is like - say, trying to say hockey and rugby are the same, afterall, they are both played with a ball!! I suppose something like an "automated, electronically controlled, dual unit manual gearbox, twin multi-plate oil-bathed clutch, with sport mode and sequential manual shift mode" is actually a bit of a mouthful!!! As we were!
Rgds
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All useful info thanks - just for the record I never suggested that the DSG had a torque converter. I put a link in explaining what goes on in an automatic (as oppose to the DSG) - honest :laugh:
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All useful info thanks - just for the record I never suggested that the DSG had a torque converter. I put a link in explaining what goes on in an automatic (as oppose to the DSG) - honest :laugh:
OK - no worries - I just didn't want people to get any confusion between the two systems. :wink:
Rgds