Known problems with T6

[David in Salop]

Hi,

I have a 67 plate 150 dsg California.

Today my engine management system warning light came on and the engine went in to safe mode and then started juddering, as I was on a straight stretch of road I stopped and called the AA. When he arrived he did a system management check and called VW. After various questions etc it turned out to be a known fault and can be solved by turning the engine off and back on again then the computer will reset itself and all is ok. The problem is caused by driving down hill, taking your foot off the accelerator and the engine over running and causing the system to go into safe mode. Apparently it is a rare occurrence, all conditions have to be met for it to happen. VW are apparently working on a patch to correct this. I usually drive with the coasting option on so the problem hasn’t occurred before today, as I was driving over Hardnott pass I had turned the coasting function off and not on again before driving on and I think this caused the problem.

I searched other posts and couldn’t see this problem so thought it was worth sharing.

Regards
David

 

[Sandyvan]

Welcome and thanks

 

[pjm-84]

Yikes.

If I'm holding a gear on a steep descent I will slow cadence brake when the revs go over 3500rpm just to give the engine a little help.

 

[Borris]

I had something similar happen whilst on holiday abroad last year. It went into limp mode and started juddering. As you say it cleared itself after the ignition was switched off and back on. I never did find the cause.

 

[Jay20cali]

Is this just a dsg problem ??
What is coast mode??
Is it a dsg thing.

 

[David in Salop]

Is this just a dsg problem ??
What is coast mode??
Is it a dsg thing.

Sorry I don’t know if the problem is only dsg or manual gearbox as well. If the same engine management system is used for all Californias I assume it is a potential problem for all. As I said it is a rare problem and switching the engine off and on again resets the computer so it is an annoyance rather than a journey stopping problem.

Re coasting mode, yes it is a dsg thing which uses the vehicle momentum to save fuel however sometimes it is better to drive with the coasting function disengaged. There is a section in the owners manual which explains it better than I can.

 

[B J G]

Problem seems to pop on T5-T6 van drivers Facebook fairly frequently. Doesn't seem to have a specific fault cause and switch off-on clears it. Leaves a worry though.

 

[soulstyledevon]

I don’t think it’s wise to use Coasting on a mountainous pass...?
I could be wrong, but I would disable and allow the engine to brake/slow the vehicle down on descents that are steep.

 

[Jay20cali]

This must be just dsg as I’m certain our last manual didn’t have any buttons saying coast mode?
The only coast mode in our 150manual was me going into coast mode as we get near the sea!!
Out come the flip flops !
(coast mode activated)

 

[WelshGas]

I don’t think it’s wise to use Coasting on a mountainous pass...?
I could be wrong, but I would disable and allow the engine to brake/slow the vehicle down on descents that are steep.

Just change to Sport Mode on the DSG. More engine braking, higher rev range before change up and Coast automatically disabled.

 

[hirsty]

Just change to Sport Mode on the DSG. More engine braking, higher rev range before change up and Coast automatically disabled.

Yes - exactly the opposite way around. The way I read the OP was that *not* using DSG Coasting was causing the engine to over-rev and go into limp mode.

I'm off over the Alps again next month & I make good use of Sport Mode, with this new info I shall be more cautious on over-revving in lower gears downhill & shan't panic if I overdo it and need to turn-it-off-and-turn-it-on-again ... Thanks for the tip.

 

[No_heroes]

Coast is horrible. Disable immediately. I actually find it dangerous as the van can runaway on a downhill. I had the unfortunate experience of driving a Porsche Cayenne with ceramic brakes with coast permanently on. Unable to drive it smoothly on a motorway.

Maybe I’m old school- but leveraging engine braking is a skill that enables gentle, smooth and forward thinking driving.

 

[WelshGas]

Coast is horrible. Disable immediately. I actually find it dangerous as the van can runaway on a downhill. I had the unfortunate experience of driving a Porsche Cayenne with ceramic brakes with coast permanently on. Unable to drive it smoothly on a motorway.

Maybe I’m old school- but leveraging engine braking is a skill that enables gentle, smooth and forward thinking driving.

Totally Disagree. Modern Diesels have very poor engine braking capability and the Coast Function is becoming common on many modern automatic vehicles. The fact that you don’t like it and can’t cope with it is just that, a personal problem.

 

[Sandyvan]

Wished they had exhaust brakes (Jake brake) like on trucks.

 

[MartG]

An alternative to sport mode is to flick the gear to the right, into manual mode - it forces the clutch to engage drive at all times. If you need more engine braking, just drop it down a gear by flicking it... back to the left for coasting once off the slopes.
Dabbing the brakes also takes it out of coasting until you re-accelerate.

Now used to the DSG, I really like it, it just needs a bit of understanding its foibles!

 

[Sandyvan]

Wished they had exhaust brakes (Jake brake) like on trucks.

Used to have a great Jake brake on my Truck, If you accelerated then pushed the foot button then accelerated the upright stacks used to smoke nice. O simple things

 

[Kernowboy]

Or just touch the brakes. Puts it back in gear and out of coast mode. Don't see the issue here.

 

[soulstyledevon]

I quite like coast mode. Wasn’t to keen initially, but you get used to it and I now use it to my advantage.
Tap of the brakes if the vehicle is getting away a bit and then a tap on the accelerator when you want to re-engage coast function.

 

[hirsty]

Good tips there to either nudge it across into Manual, or down into Sport to cancel coasting / engage engine braking.

Dabbing the brakes works of course, but on motorways it contributes to ripple effect & the poor sods miles back might end up in a phantom jam for no good reason. Same goes for 'coming off' cruise control with the brake pedal.

Traffic wave - Wikipedia

en.wikipedia.org

 

[soulstyledevon]

Dabbing the brakes works of course, but on motorways it contributes to ripple effect & the poor sods miles back might end up in a phantom jam for no good reason. Same goes for 'coming off' cruise control with the brake pedal.

Traffic wave - Wikipedia

en.wikipedia.org

You shouldn’t need the brakes on the motorway unless you really are coming to a stop.
Awareness needed behind as much as in front when travelling at speed on a motorway.

 

[zinglefiffy]

my dsg will quite often reengage the clutch by itself if i'm coasting down an incline. going by comments here, is this a new thing?

 

[MartG]

my dsg will quite often reengage the clutch by itself if i'm coasting down an incline. going by comments here, is this a new thing?

My new Ocean will do that to, I don't know if it's detecting incline or driving style or just random! but it seems to be correct in it's deployment so I'm happy...

 

[Geoff York]

Coast is horrible. Disable immediately. I actually find it dangerous as the van can runaway on a downhill. I had the unfortunate experience of driving a Porsche Cayenne with ceramic brakes with coast permanently on. Unable to drive it smoothly on a motorway.

Maybe I’m old school- but leveraging engine braking is a skill that enables gentle, smooth and forward thinking driving.

I’m an hgv driver...... never use the engine for braking
“ gears are for going.........brakes are for slowing “
Police drivers are also trained this way

 

[Spottydog]

I haven’t encountered this with the dsg gearbox but the comfortmatic on the Fiat Ducato does this every time it goes downhill. I’ve tried everything and nothing seems to stop it. Hope the dsg doesn’t start too.

 

[Terence Kirton]

Hi,

I have a 67 plate 150 dsg California.

Today my engine management system warning light came on and the engine went in to safe mode and then started juddering, as I was on a straight stretch of road I stopped and called the AA. When he arrived he did a system management check and called VW. After various questions etc it turned out to be a known fault and can be solved by turning the engine off and back on again then the computer will reset itself and all is ok. The problem is caused by driving down hill, taking your foot off the accelerator and the engine over running and causing the system to go into safe mode. Apparently it is a rare occurrence, all conditions have to be met for it to happen. VW are apparently working on a patch to correct this. I usually drive with the coasting option on so the problem hasn’t occurred before today, as I was driving over Hardnott pass I had turned the coasting function off and not on again before driving on and I think this caused the problem.

I searched other posts and couldn’t see this problem so thought it was worth sharing.

Regards
David

Thanks David - I had a similar problem after descending a steep hill. The Beach juddered and came to a halt as I climbed a steep incline. It sorted itself when I switched off and rested for half a minute. I put it down to gravel caught up in the brakes. Now I realise what it was! Terry