Oil alert

[blondebier]

Edit: I try not to stop the engine when it’s is part way thorough a regen

Surely the "software fix" should let the regen continue when the engine is turned off. (Like it does on the T6)

Why does it stop when the engine is turned off?

 

[Perfectos]

Just depressed myself reading a couple of threads on the T6 forum about high oil levels and fuel contamination AND VW’s total inability to resolve the issue for all affected owners.

What really concerns me is the potential for engine damage if the oil is getting diluted with diesel fuel. I’ve got a 5-year warranty but intend keeping the van much longer, so it matters to me.

Even though i’ve not yet had this issue I am shocked to read that so many other owners have it - some with new low mileage vans.

I’m awaiting a response from a Van Centre but unless they advise of a forthcoming ‘fix’, I intend to try and get a statement in writing from VW with appropriate assurances.

Not ideal but you can change your engine oil with much greater frequency to help reduce the “Dilution“ effect.

It seems that there is no such thing as a free lunch when it comes to these emissions measure. Just about everything introduced to “solve” an issue (pollution) introduces issues in other areas and problem with the overall power train, engine tuners are well aware of this!
“Tech“ does not necessarily mean efficient and reliable engines!

 

[GrumpyGranddad]

Surely the "software fix" should let the regen continue when the engine is turned off. (Like it does on the T6)

Why does it stop when the engine is turned off?

If I understand it correctly, when a regen’ starts diesel is introduced into the cylinder on the exhaust stroke so it’s obviously unburnt diesel. The intention is that the unburnt disel then arrives in the DPF and then ignites and raises the temperature to burn off the particulates. If the engine stops and even if the regeneration continues then the unburnt diesel that is sitting in the cylinder(s) can seep into the oil sump.
Is that a correct understanding?

 

[blondebier]

The new fuel injection strategy in the T6.1 system sounds like it needs finishing off.

In the attached promotional material it says:

Transporter owners will have the option to trigger the regeneration of the diesel particulate filter manually via a new button in the cockpit. While DPF regeneration happens automatically, in the case of vehicles that are permanently doing short distances (e.g. mail and parcel delivery) or constantly moving at speeds of under 25mph (e.g. special vehicles at airports) this automatic process does not kick-in in day-to-day operation. With the new (optional) DPF independent regeneration funtion, the trigger can now be activated manually.

Perhaps VW need to make this feature standard across the T6.1 range. Pronto, by the sounds of it!

 

[blondebier]

The attachment was too large. See here:

https://www.vwpress.co.uk/assets/documents/original/24814-T61packFinal4.pdf

 

[Kernowboy]

If I understand it correctly, when a regen’ starts diesel is introduced into the cylinder on the exhaust stroke so it’s obviously unburnt diesel. The intention is that the unburnt disel then arrives in the DPF and then ignites and raises the temperature to burn off the particulates. If the engine stops and even if the regeneration continues then the unburnt diesel that is sitting in the cylinder(s) can seep into the oil sump.
Is that a correct understanding?

Not aware of any difference between T6 and T6.1 in this regard, both regen same way; issue has been reported in both.

 

[CampervanTime]

Well, I've been continuing the conversations with the VW Master Tech today and have done some more testing on my own Cali this evening.

From stone cold measurement on the dipstick (about 2/3 full on the hatched section), then drove it for 1hr40, oil at 105c when turning off. Left it for 5 mins then dipped oil - was right to the top of the hatched section on the dipstick.

Tomorrow morning when stone cold I will check it again.

I've taken photos so I don't guess or forget overnight!!

My aim is to try to do a (probably anonymous) zoom chat with the Master Tech to share on our channel, where I ask him what the problem is, what the software fix does, why it does it and if it is related to DPF regens or not.

I have no issue in being corrected on these matters of course - but am keen to see it with my own eyes.

There is more I have been told that I don't want to say on here yet which is positive stuff and credible explanations, but want to finish my conversations in the background first.

 

[Perfectos]

From stone cold measurement on the dipstick (about 2/3 full on the hatched section), then drove it for 1hr40, oil at 105c when turning off. Left it for 5 mins then dipped oil - was right to the top of the hatched section on the dipstick

That would concur with the Oil being correctly filled, allowing for expansion of the oil from below the max line when the engine is cold (on the dip stick) to the Max Line during normal use.

The Hatched area on the dipstick represent approximately 1 litre of oil, so if my calculations above are correct, your engine oil would show at the maximum mark on the dipstick when the engine is upto operating temp. (I.e full engine oil volume increases by about 400ml at normal operating temp)

edit: obviously any increase in sump volume from the “diesel” in passing to the sump situation will increase the sump volume and potentially increase the oil level to overfill!

 

[Perfectos]

What really concerns me is the potential for engine damage if the oil is getting diluted with diesel fuel. I’ve got a 5-year warranty but intend keeping the van much longer, so it matters to me.

FUEL DILUTION OF ENGINE OIL: CAUSES AND EFFECTS

lubricants.totalenergies.com

“As for light-duty vehicles, several cases have been observed in which the oil level increased instead of decreasing, resulting in several instances where the level far exceeded the maximum mark on the dipstick. Although this may seem like good news, it is not: in such instances, not only does the same dilution problem occur, but it is also particularly serious, given that in such cases the concentration of fuel is very high and can cause rapid wear and engine failure. Occasionally you may detect a drop in pressure and/or power if this is the case.

Some manufacturers have actually added a new notch above the maximum mark as a warning sign. If you notice an increase in the excess level, you should reduce the mileage interval for changing the lubricant by half. This instruction is included in the maintenance manual of the vehicle and must be observed in order to maintain the warranty.

Furthermore, as the lubricant is being used up (1 liter per 10,000 kilometers) and replaced by fuel, the concentration of additives decreases, meaning that part of their protective action of the engine is lost.

In the specific case of diesel cars, diesel fuel also enters the crankcase as a result of post-injection during regeneration so that the fuel gases can reach the crankcase and help the regeneration process by providing heat. As not all diesel fuel turns to gas, part of the fuel enters the crankcase, which produces the dreaded oil dilution.”

 

[sidepod]

That makes interesting reading

“Cut the oil service schedule in half”

What is the duty cycle of your van OP?
Are you using it for short journeys and therefore causing many regens?

I like the “manufacturers adding an extra notch on the dip stick. Genius.

 

[sidepod]

I wouldn’t worry about high oil levels, once your crankshaft oil seals start leaking, it’ll go down again

 

[Perfectos]

That makes interesting reading

“Cut the oil service schedule in half”

What is the duty cycle of your van OP?
Are you using it for short journeys and therefore causing many regens?

I like the “manufacturers adding an extra notch on the dip stick. Genius.

I was under the impression that from the T6 onwards they have been fitted with a sensor to sense when oil quality drops below a certain threshold.

If this latest issue is due to diesel dilution to the extent that it throws up an over fill warning, then why is the oil quality sensor not throwing up a fault as well ?

 

[Holidaymaker]

So much writing when is little extra or little less oil, - make more or take away too much - how is peoples make such complicated problem?


I having extra water my fridge but if I say such situation, maybe I am give chart picture and graph explain why is such water my fridge!

 

[Perfectos]

So much writing when is little extra or little less oil, - make more or take away too much - how is peoples make such complicated problem?


I having extra water my fridge but if I say such situation, maybe I am give chart picture and graph explain why is such water my fridge!

I think you just answered your own question!

 

[CampervanTime]

That would concur with the Oil being correctly filled, allowing for expansion of the oil from below the max line when the engine is cold (on the dip stick) to the Max Line during normal use.

The Hatched area on the dipstick represent approximately 1 litre of oil, so if my calculations above are correct, your engine oil would show at the maximum mark on the dipstick when the engine is upto operating temp. (I.e full engine oil volume increases by about 400ml at normal operating temp)

Yep - which would suggest that the oil level should be filled to approx half way on the dipstick when engine is cold - and I suspect my van was PDI'd and the oil level filled to the top of the hatched section when cold - seemingly incorrectly.

Plenty more to come on this I think...

 

[Perfectos]

Yep - which would suggest that the oil level should be filled to approx half way on the dipstick when engine is cold - and I suspect my van was PDI'd and the oil level filled to the top of the hatched section when cold - seemingly incorrectly.

Plenty more to come on this I think...

I literally just picked my van up from an oil service.

I will look tomorrow and report back accordingly.

surely the factory fill the engine oil, to the “factory” measure,
the PDI is presumably a visual check by the dealer, to ensure the oil level is showing on the dip stick ?
from what you suggest, I wonder if some dealers are then topping up the engine oil above the factory measure?

 

[CampervanTime]

Well - that is certainly what the master tech I've been talking to is saying he is seeing. He has to PDI new vehicles and they are coming from the factory with the oil half way on the dipstick (and it appears it should be left like this), whereas some techs have been topping it off because they think it was a factory error - where it is not.

Will be interesting to see what level yours has - although it might be different for a T6 than a RDE1 or RDE2 T6.1 possibly...

 

[Perfectos]

Well - that is certainly what the master tech I've been talking to is saying he is seeing. He has to PDI new vehicles and they are coming from the factory with the oil half way on the dipstick (and it appears it should be left like this), whereas some techs have been topping it off because they think it was a factory error - where it is not.

Will be interesting to see what level yours has - although it might be different for a T6 than a RDE1 or RDE2 T6.1 possibly...

Interesting Comment.
I would have thought VW GMBH would have looked into the variables before committing resources for an ”update” particularly as the issue appears to be a relatively common issue!
if it were / is dealer error, I would imagine a bulletin to clarify not a software update ?

I would expect the dipstick normal oil range “hatched marker“ would be similar from T6 - T6.1 even if the dipstick has changed (which I think it has)
T5.1 - T6 was very similar and the min Max marks were about one litre difference.
The engine oil will have always expanded on every vehicle ( predictably so) so I can’t see that be something that has suddenly caught out dealers? IMO Dealers would not add oil without reason as it costs the dealer to do so & I assume there would be a reciprocal agreement with VW that allows the dealer to claim back costs for such instances (or maybe a flat fee for each PDI) either way I cannot see dealers suddenly starting to to
up engine oil in a way I doubt they did in the past ?

 

[GrumpyGranddad]

I literally just picked my van up from an oil service.

I will look tomorrow and report back accordingly.

surely the factory fill the engine oil, to the “factory” measure,
the PDI is presumably a visual check by the dealer, to ensure the oil level is showing on the dip stick ?
from what you suggest, I wonder if some dealers are then topping up the engine oil above the factory measure?

Mine had an oil change service last week so will check the level in the morning too.

 

[CampervanTime]

Can't answer that as I've not spoken to any other VW techs about this and what is/was common practice.

The understanding I have (now) is that the software fix is more about allowing a greater tolerance for high oil level above the top of the hatched area on the dipstick when the oil is warm. I have no idea how this works (ie if it changes what level it looks for depending on oil temp too) but that is my understanding of the change. And.. apparently this is only available for RDE1 engines not RDE2 yet although they are working on it.

 

[sidepod]

Can't answer that as I've not spoken to any other VW techs about this and what is/was common practice.

The understanding I have (now) is that the software fix is more about allowing a greater tolerance for high oil level above the top of the hatched area on the dipstick when the oil is warm. I have no idea how this works (ie if it changes what level it looks for depending on oil temp too) but that is my understanding of the change. And.. apparently this is only available for RDE1 engines not RDE2 yet although they are working on it.

So literally just a shorter dipstick!! That’s not solving the problem is it, that’s just changing the way you measure it ffs

 

[CampervanTime]

So literally just a shorter dipstick!! That’s not solving the problem is it, that’s just changing the way you measure it ffs

Well, I can see some logic in it as if it genuinely is oil expansion when hot that is triggering the 'reduce oil level' warning and this is too sensitive at the moment, then the software fix will help with that - as would a physically shorter dipstick too of course as long as the oil fill level was actually adjusted to fit it too.

I did come across some articles online about a Golf model (I think) where VAG did issue a new dipstick for it...

 

[sidepod]

I’m not sure about the oil expansion theory or calculations, impossible to predict without a perfectly linear/known sump shape.

 

[CampervanTime]

Well, all I can do is go on what I have seen and tested with my own eyes - on the same driveway, parked in the same position, tested cold / hot / cold.

I tested the cold/hot last night but just waiting for it to get light this morning and I'll check the cold again to see if my oil level has returned back to yesterdays cold level.

 

[andyinluton]

Well, I can see some logic in it as if it genuinely is oil expansion when hot that is triggering the 'reduce oil level' warning and this is too sensitive at the moment, then the software fix will help with that - as would a physically shorter dipstick too of course as long as the oil fill level was actually adjusted to fit it too.

I did come across some articles online about a Golf model (I think) where VAG did issue a new dipstick for it...

You would need a longer dipstick rather than shorter so that less oil is put in.

It might be oil expansion that triggers the warning, but something ie diesel must have increased the volume in the sump as well, otherwise the warning would happen the first time the oil got hot.

It would make sense to mark the dipstick with the level when cold. Checking when hot has too many variables, how hot? too soon after stopping and too much oil is still to drain back to the sump.