Auto hold - DSG - burning clutch?

[AllBlack]

Hoping someone is in the know...

Here's the scenario. Start stop is on and auto hold is on. Sitting at the lights, after taking your foot off the brake, the engine starts again but auto hold prevents the car from moving forward. In this scenario, I understand the brake is held but is the clutch burning ready to take off or is it sitting in nutral? Currently I avoid having the car stationary with the auto hold function on fearful of burning the clutch.

[Guest001]

Hoping someone is in the know...

Here's the scenario. Start stop is on and auto hold is on. Sitting at the lights, after taking your foot off the brake, the engine starts again but auto hold prevents the car from moving forward. In this scenario, I understand the brake is held but is the clutch burning ready to take off or is it sitting in nutral? Currently I avoid having the car stationary with the auto hold function on fearful of burning the clutch.

Far better to use stop start and keep your foot hard on the brake till just before the lights change then lift a bit for the engine to start just as they change and off you go Dont bang your foot straight on the loud pedal or you will next be growling about rough starts. Give it a sec to fire up properly. Its just a matter of getting used to it and learning to anticipate a bit
As you have found out foot braking and auto hold are rather different and the stop start and auto hold dont go together.

I NEVER use it possibly because there are no hills where i live.

[AllBlack]

Thanks Hillbilly. Reason I ask is that it applies to me when I'm approaching the lights and I know they are about to turn green but I'll be stationary for 4 seconds so don't really want the engine to turn off. I come to a stop but remove my foot from the brake to keep the engine running. Hence, could be burning clutch.

[toto]

You can turn off start/stop. Also braking with light pressure stops the start/stop engaging.

Fairly certain that auto hold does not ride the clutch. I believe it holds car until you apply the accelerator, when forward momentum is applied via the accelerator, that is the force which disengages the auto hold.

[Guest001]

Thanks Hillbilly. Reason I ask is that it applies to me when I'm approaching the lights and I know they are about to turn green but I'll be stationary for 4 seconds so don't really want the engine to turn off. I come to a stop but remove my foot from the brake to keep the engine running. Hence, could be burning clutch.

As Toto said just dont put the brake on so hard and the engine wont stop but will still hold you still The Stop Start can only be turned off during each journey but Hold can be turned off permanently.
You can drift up to the lights with the brakes on but not hard enough to stop the engine and car wont move.

You will learn by experimenting. Same when you have the handbrake on You just accelerate gently and it automatically releases or havent you found that out yet will only do it with drivers seatbelt fastened. Dont think clutch engages till revs build a bit

[Lindsay]

As far as I know, when auto hold is engaged the car uses light brake pressure to keep you from inching forward. So you would think the transmission would be in neutral.... There shouldn't be any need for it to be riding the clutch as it can release it fairly quickly anyway...
Also, after a certain amount of time 'auto holding', the electric park brake takes over and engages itself.

[Guest001]

As far as I know, when auto hold is engaged the car uses light brake pressure to keep you from inching forward. So you would think the transmission would be in neutral.... There shouldn't be any need for it to be riding the clutch as it can release it fairly quickly anyway...
Also, after a certain amount of time 'auto holding', the electric park brake takes over and engages itself.

My understanding is that it applies the handbrake and releases it as you put your foot on the accelerator . The handbrake light does not come on however
The clutches are operated electrically by solenoids so are fairly instant in their uptake. I have sat talking with my foot on the brake for 10 mins and have no hot smells but then the Passat has wet clutches so is more amenable to that. The 7sp Dry clutches are the problem for heat.

[nyc863]

the auto hold isn't using the handbrake, I think, because you can hear the handbrake motor it takes a long time to apply and a long time to un-apply the brake, this is something you do not hear with auto-hold. I would bet it uses the ABS system to hold the brakes on, and no it doesn't ride the clutch.

[Guest001]

the auto hold isn't using the handbrake, I think, because you can hear the handbrake motor it takes a long time to apply and a long time to un-apply the brake, this is something you do not hear with auto-hold. I would bet it uses the ABS system to hold the brakes on, and no it doesn't ride the clutch.

You actually are correct See this page

Auto Hold Function < Technical Glossary < Innovation & Technology < Volkswagen International Slight difference in that in the Passat it can be turned on all the time????

Im sure a good read of this page by new owners will save a list of questions about the vehicle


Perhaps the admin may like to make a sticky out of it as it describes all the different functions of the vehicles Probably better than the cars manual

http://en.volkswagen.com/en/innovati...-glossary.html HOME PAGE FOR IT

[kleung]

I have sat talking with my foot on the brake for 10 mins and have no hot smells but then the Passat has wet clutches so is more amenable to that. The 7sp Dry clutches are the problem for heat.

To my knowledge, when stationary, with the selector in any position other than P or N, on the brakes or with the handbrake engaged, the gearbox has first gear (or reverse gear) selected, and the clutches are disengaged. The clutches engage when you use the accelerator, or motion is detected.

You can test this for yourself. Disable stop/start and autohold, stop on an incline. When you release the brakes, you'll feel the car roll backwards for a fraction of a second before the clutches engage and slow or stop the rollback. The effect can be disconcerting if you're not expecting it, especially when reversing, but you can mitigate the effect with auto-hold.

[Guest001]

To my knowledge, when stationary, with the selector in any position other than P or N, on the brakes or with the handbrake engaged, the gearbox has first gear (or reverse gear) selected, and the clutches are disengaged. The clutches engage when you use the accelerator, or motion is detected.

You can test this for yourself. Disable stop/start and autohold, stop on an incline. When you release the brakes, you'll feel the car roll backwards for a fraction of a second before the clutches engage and slow or stop the rollback. The effect can be disconcerting if you're not expecting it, especially when reversing, but you can mitigate the effect with auto-hold.

The hill start assist governs the starting torque when pulling away on an uphill incline and interacts with the hydraulic brake assist and the transmission control to prevent the vehicle from rolling backwards by applying the brakes. This makes controlling the vehicle during hill starts simple and convenient for the driver. So there is no need to worry about the vehicle rolling backwards or the engine stalling.

From the technical page of VW

[wai]

Hoping someone is in the know...

Here's the scenario. Start stop is on and auto hold is on. Sitting at the lights, after taking your foot off the brake, the engine starts again but auto hold prevents the car from moving forward. In this scenario, I understand the brake is held but is the clutch burning ready to take off or is it sitting in nutral? Currently I avoid having the car stationary with the auto hold function on fearful of burning the clutch.

No, the clutch will not start engaging until the system detects a change in accelerator position. At that point the brake will disengage and the clutch engage.

With a DSG, you do NOT want to try and hold the vehicle n the hand brake only as now the clutch will try and engage. You have to have your foot on the brake where a sensor will disengage the clutch.

[Creniac]

Here's a scenario I experienced many a time in my Jetta.... I have a steep driveway, I would often pull up the driveway, use the autohold feature to hold me in position while my son reached into the letterbox to collect mail.... it was about now I realised a huge issue with auto hold... I'm not sure what sensors come into play but as I tried to accelerate away the autohold feature would not let go although I was throttling on... yes I had the 7DSG but the autohold refused to let go many a time... After experiencing the autohold locking me down a few times I got the sh*ts to say the least.... each time engine revs increased and the horrid smell of clutch burn entered the car..... I eventually had to avoid this and walk back down the driveway to collect the mail in fear of burning the clutch pack out!
I have since got rid of this car due to many issues experienced with it... not only this issue but the fact the DSG mechatronics issue got me as well..... good news is I still love VW now that I have a manual Tiguan....

[Guest001]

Here's a scenario I experienced many a time in my Jetta.... I have a steep driveway, I would often pull up the driveway, use the autohold feature to hold me in position while my son reached into the letterbox to collect mail.... it was about now I realised a huge issue with auto hold... I'm not sure what sensors come into play but as I tried to accelerate away the autohold feature would not let go although I was throttling on... yes I had the 7DSG but the autohold refused to let go many a time... After experiencing the autohold locking me down a few times I got the sh*ts to say the least.... each time engine revs increased and the horrid smell of clutch burn entered the car..... I eventually had to avoid this and walk back down the driveway to collect the mail in fear of burning the clutch pack out!
I have since got rid of this car due to many issues experienced with it... not only this issue but the fact the DSG mechatronics issue got me as well..... good news is I still love VW now that I have a manual Tiguan....

Auto hold and Hill start assist are two different things Auto hold can be turned on and off Hill start is built in and works automatically.

Auto hold works as part of the Electric handbrake and Hill assist works with the Hydraulic braking

Have a read of this page Auto Hold Function < Technical Glossary < Innovation & Technology < Volkswagen International

If you are only stopping for half a minute I would have just kept my foot firmly on the footbrake.

[wai]

I have the exact opposite with my Caddy.

I stop on a hill facing uphill and try ad drive up. I press the brake pedal to engage hill hold and the pedal comes up hard. I take my foot off the brake and press the accelerator. The brake releases immediately and the clutch engages around 1/4 second later. The result is I roll back a little. Not too bad.

I stop on a hill facing downhill and try and reverse up. I press the brake pedal to engage hill hold and the pedal comes up hard. I take my foot off the brake and press the accelerator. The brake releases immediately and the clutch takes around 1 second to engage. I start rolling forward, so my reaction is to press the accelerator a bit more. The clutch engages and I am launched backwards. I jump on the brake and the loop starts again.

The only way around this is to use the handbrake (conventional type) and use it the same way you would with a manual transmission.

Now there are two types of hill assist. One is called hill hold, and the other called hill start.

The hill start version is supposed to release the brake gradually rather than instant off. It will also hold the car with your foot off the brake for up to 3 minutes. The clutch is not engaged until accelerator position changes.

The hill hold version releases the brake instantly. It will also hold the car with your foot off the brake but for just 3 seconds. The clutch is not engaged until 1 second after accelerator position changes.

The sensor that is used to work out when to release the brake is the one that detects accelerator position.