Increasing Oil Level on BiTDi??

[john2107]

Just back from a 2000 mile tour around France with my 3.0 BiTDi. Fantastic car. One question however:

Now done 28k miles, first service was at 21k. After the service I checked the oil level on the MMI display and noted it was below the full mark, around 3/4. I checked a few days afterwards and it was the same. Interestingly the Audi dealer who serviced it didn't put it back on an extended service interval despite my request.

Anyway, I have now checked again, 7k miles later and find the oil level to be up to the maximum level. Now, we have a diesel Volvo in the family and I know they are prone to oil level increasing due to unburnt diesel finding its way back into the sump as a result of the DPF regen process. (This was subject to a Volvo recall I believe, and advice on oil changes is now to fill to the 2/3 mark, to avoid triggering a fault warning light).

So my question, is the Audi 3.0 BiTDi prone to this as well? Mine seems to run a lot of DPF regen cycles despite being a high mileage car. Does this have anything at all to do with the apparently increasing oil level?

Any thoughts anyone?

[chesterfield]

In my experience oil level will change dependent on temperature of engine. If its been running a while, a lot of it will find its way into various parts of the engine. If its only just been started or is checked when cool, all that oil will have drained back to the sump hence the different readings.

[ukgroucho]

And mine did the same... after first service around 10k I was surprised to see oil level as below 'full'. Checked it a couple of thousand miles later and it showed full.

I don't think there is an issue here.. as chesterfield points out what you see on the meter will vary depending on how long the car has been standing, temperatures etc.
So long as it is above half full I would not be concerned.

Of course they could ALL be slowly filling up the sump with unburned diesel :O

[shabazmo]

Its best to check it manually with a dipstick. You will have to buy one from ebay and get the calibration sheet which I can send to you.

[Herbie1213]

Just a word of caution the MMI only represents the part of the oil dip stick which would be used to check oil levels. The difference between the top and bottom marks on the dip stick represents about 250 ml of oil. Oil levels will vary from time to time so as a post above states as long as it is above half full I would not be concerned.

The only way to check oil consumption is to weigh the oil before it is put in the engine then use the car for an agreed 'n' of miles drain the oil and weigh again.

[shabazmo]

The difference between top and botton marks on a dipstick is 1 litre. It is the same with the MMI readings. Unless someone knows better.

[JimC64]

Just back from a 2000 mile tour around France with my 3.0 BiTDi. Fantastic car. One question however:

Now done 28k miles, first service was at 21k. After the service I checked the oil level on the MMI display and noted it was below the full mark, around 3/4. I checked a few days afterwards and it was the same. Interestingly the Audi dealer who serviced it didn't put it back on an extended service interval despite my request.

Anyway, I have now checked again, 7k miles later and find the oil level to be up to the maximum level. Now, we have a diesel Volvo in the family and I know they are prone to oil level increasing due to unburnt diesel finding its way back into the sump as a result of the DPF regen process. (This was subject to a Volvo recall I believe, and advice on oil changes is now to fill to the 2/3 mark, to avoid triggering a fault warning light).

So my question, is the Audi 3.0 BiTDi prone to this as well? Mine seems to run a lot of DPF regen cycles despite being a high mileage car. Does this have anything at all to do with the apparently increasing oil level?

Any thoughts anyone?

Can't day definitively, but have the same awareness on my Jaguar, especially when completing a lot of short start stop journeys..........the oil level will rise and for the reasons you say

The trick is on the Jaguar anyway, at oil change time, always only ever fill to just under halfway between min - max and keep an eye on it.
I usually go for mid way oil changes and use National Tyres, cost around £40 using the correct grade of oil too.

[wja96]

This isn't an issue I was previously aware of (particulates building up in the sump) so thanks for bringing it up.

My oil level dropped to about 75% in the first 4,000 miles and stayed there. It hasn't moved from 100% since the oil was refilled at the first service.

if you are worried about the DPF then there are various DPF parameters that can be read with VCDS if you have access to that software.

Without actually going and plugging the car in, I don't think there is any way to check the oil quality with VCDS, but you effectively have access to everything a VAS machine does, so if the car is monitoring it, VCDS should be able to tell you.

i would class myself as a high mileage driver but I don't always use the allroad. When I do though, it almost never gets turned on and does less than 200 miles before being shut down. In almost 9 months of ownership and 18,000 miles I believe it has only triggered a full regen once, but they do a regen check every 600 miles/1000km and they have a DPF life of roughly 120,000 miles or 200,000km so in theory they could do a LOT of regenerating. If it adds some particulates to the sump every regen then it would indeed be wise to change the oil more frequently and limit the amount added. I would have hoped that Audi would have been aware of this during the development of the car and allowed for it though, but then again.... This is VAG we're talking about!

By virtue of the fact it's a biturbo the BiTDi should be a low soot engine because the bigger secondary turbo allows for LOTS of air higher in the rev range to keep the air/fuel optimised.

As for not swapping your car to long life servicing I was told that I could only do it at the second/main service, not on an oil change service so they wouldn't do it at 9000 miles but they will (hopefully) do it when my car goes in next.

[M1tchy]

Its best to check it manually with a dipstick. You will have to buy one from ebay and get the calibration sheet which I can send to you.

Mine doesn't have a dipstick. Only the MMI readings.

[MarkTM]

^^^ You have to order one from Audi, at present yours will have a blanking plate/plug where the dipstick will go.

Personally, given the proven vaguaries/inaccuracies of MMI in general, I'd prefer to do it the old fashioned way so when I get my BiTDi (either A6 or A7) the dipstick is one of the first things I'll be ordering :)

You can virtually guarantee that when it's in for a service the mechanic won't be using the MMI.

[wja96]

I've just re-read the original post and I've just realised that your car WAS on long-life servicing and it seems they switched it to annual/periodic. If that's the case I'd be very unhappy with the dealer and I wouldn't be paying for the intermediate service, especially if you asked for it to be left on long-life.

It does seem very odd.

I have just been in to Crewe Audi and ordered a dip stick. That was an interesting conversation - I can assure you.

"You want what? What happened to the old one? It doesn't have one? I'm sure it does. Let me get a technician to show you where it is"

5 mins later...

"that'll be £19 plus VAT"

:)

[MarkTM]

^^^Hilarious...good to see they know the cars they sell :biglaugh:

My personal preference given the feedback on LLS on the C6 forum, I'd always opt for fixed interval, unless of course I was doing the 17k+ miles each year mainly M'way. Even then I'd probs do a oil and filter change halfway through to keep everything clean.