Oil usage

[SR71]

think you've missed my point about FSI not being the cause of high oil consumption - I've experienced the same behaviour regarding oil consumption (2 litres in the first 5K miles, 1 litre in the second 5K miles, then negligible afterwards) in 5 Audis - a 1.8T 225, a B6 S4, a 1.9 TDi 130, a B6 S4 (again) and a B7 RS4. and ONLY one of those has FSI ( and one was a diesel). So FSI has made no difference at all to the oil usage I've experienced.

I can see why you think FSI isn't an issue but logically your conclusion is a non-sequiter...for various reasons.

It may or may not be an issue...I have no idea.

I'll be checking my oil when it is next dropped to see whether I see the same kind of reduction in flash point because, regardless of the usage issue, thats bad.

The dealer told me the RS4 must be filled with their long life oil and can be topped up with Mobil 1 or other full synthetic oil but not as a whole oil change. That must be their "myth" to use their oil at oil change???

If you read Oilman's comments on the Opie Oil WWW site, you'll see that this is BS. Mixing oils with the same basestock (i.e., mineral or synthetic) isn't an issue. Even mixing oils of differing multigrades isn't a big deal within reason. Personally in a UK climate, if you do do this, I think its more important to match the low temperature grades rather than the high temperature grades i.e., mixing a 5w-30 and a 5W-40 is OK but I'd be less inclined to mix a 5W-30 with a 10W-30.

Those of you seeing 120+C at the track are you using a 5W-30 oil?

[AntoRS4]

Those of you seeing 120+C at the track are you using a 5W-30 oil?

Castrol 5W30 EDGE 504.00 507.00

[PetrolDave]

[quote="SR71]I can see why you think FSI isn't an issue but logically your conclusion is a non-sequiter...for various reasons.[/quote]
Logically I disagree with you. The evidence I gave shows that FSI is not a factor in oil usage.

Care to share the reasons you mention with us?

[SR71]

Correct me if I am wrong but you suppose that because the pattern of oil usage your non-FSI cars exhibit matches what your FSI 4.2 exhibits, then the cause is un-related to the FSI?

But couldn't an identical pattern of oil usage have a root cause that is fundamentally different...in one case FSI related in the other unrelated to FSI?

Logically, "Yes".

I'm being a pedant.

My gut feeling is the usage is a function of a mechanical cause, assisted by a chemical one, although no-one has suggested a plausible reason (which I've heard) for why an engine with such tight tolerances should burn more oil than otherwise expected.

FWIW.

[t_urbo]

Surely oil usage on a N/A car is mainly down to how well the pistons are seated, hence the reason why some RS4's use more oil than others.

In the 10,500 miles my car has done i have only topped up 2-2 1/2 ltrs of oil, but i drove mine hard from the start and have found doing the same in previous cars had the same effect of low oil usage, but then my theory may be complete BS.

[PetrolDave]

I'm being a pedant.

You certainly ARE clutching at straws ...

[audijohn]

Surely oil usage on a N/A car is mainly down to how well the pistons are seated, hence the reason why some RS4's use more oil than others.

In the 10,500 miles my car has done i have only topped up 2-2 1/2 ltrs of oil, but i drove mine hard from the start and have found doing the same in previous cars had the same effect of low oil usage, but then my theory may be complete BS.

Mine however has used 1 Litre of oil in 7200 Miles, and I have carefully run mine in without Red Lining it much in the first 3K!!
No definative answer there then.

[t_urbo]

Surely oil usage on a N/A car is mainly down to how well the pistons are seated, hence the reason why some RS4's use more oil than others.

In the 10,500 miles my car has done i have only topped up 2-2 1/2 ltrs of oil, but i drove mine hard from the start and have found doing the same in previous cars had the same effect of low oil usage, but then my theory may be complete BS.

Mine however has used 1 Litre of oil in 7200 Miles, and I have carefully run mine in without Red Lining it much in the first 3K!!
No definative answer there then.

Yes but your Man at Audi (Nicknamed the Stig) ran it in for you prior to collection

Do you do short or long trips?

[audijohn]

Surely oil usage on a N/A car is mainly down to how well the pistons are seated, hence the reason why some RS4's use more oil than others.

In the 10,500 miles my car has done i have only topped up 2-2 1/2 ltrs of oil, but i drove mine hard from the start and have found doing the same in previous cars had the same effect of low oil usage, but then my theory may be complete BS.

Mine however has used 1 Litre of oil in 7200 Miles, and I have carefully run mine in without Red Lining it much in the first 3K!!
No definative answer there then.

Yes but your Man at Audi (Nicknamed the Stig) ran it in for you prior to collection

Do you do short or long trips?

Mine never gets less than 5/9 Miles every time it gets used, mostly longer trips.

[SR71]

I'll be sending my oil here: http://www.oilanalysis.org.uk/index.html for analysis and will report back.

I'm sure that my short trips (I live 3 minutes from the airport) are one reason for accelerated usage. The oil only just climbs to 60C before I shut down again.

[Golich]

1 L first 900miles
2nd Litre @ approx 3000miles
3rd L @ approx 7000miles
Now 8000miles dip stick is 3/4 so it looks like the consumption is steadily reducing.

I was warned on picking my car up from new that it would initially use a lot of oil. The saleman said it was due to a cylinder bore lazer machining/honing process which left a small nibb which takes some time to wear away or someting like that.

[Lancia]

It would be nice if one of the Quattro GMBH design engineers were on the forum so we could get to the point rather than 3 pages of theories, guesses and urban myths.

Sorry, not having a go at anyone.

Most people make a valid point but between Audi sales and service we do hear alot of varied ideas and alot of Bullstuff!

[Voyager]

there are a million reasons why any internal combustion engine will use up its oil. if we negate mechanical wear issues and turbo's the biggest link is the one between rpm and oil consumption.
generally the higher the rpm limit (or piston accel rates due to bore/stroke) the greater the oil usage. imagine a syringe with fluid inside and a less that perfect seal on the plunger. if you slowly accelerate the plunger down the bore 99.9% of the fluid will be ejected from the nozzle. if however you push the plunger as fast as you can perhaps only 98% of the fluid will be ejected.
the RS4 has a pretty high rpm limit for its size and at these higher reaches of rpm oil usage increases far more than at the lower levels of rpm. the ring to bore gap is not perfect (nor can it or should it be) and as the piston changes direction the ring will flex in the piston allowing an increase in the film of oil left on the cyl wall. this sacrificial system prevents metal/metal contact within the bore and prevents your expensive V8 from becoming a sack of bits. the downside is slightly higher oil consumption figures at high rpm levels. i know which i prefer.

[cmathis]

1/2 liter at 1600 miles. Using RI_RS4's break in procedure.

0-700 miles = 1/2 liter (changed oil to Lubro Moly 5w-40).

700-1500 miles (no oil usage detectable on dipstick).

Changed oil again at 1500 miles (lubro moly again). Will now go to the 5000K mile checkup. Tons of black in the milltek tips, but don't seem to be pulling much out of the pan.

Craig

[rjkflyer]

Debated this with Audi dealer at length. The Audi line is that with this engine a usage as high as one litre per THOUSAND MILES is still within limits (and therefore will not receive any interest from them). The explanation is that this engine consumes the oil as part of its protective process, which is why RS4 owners will note blue smoke occasionally, especially if you start and stop the car a few times due to small manoeuvres like backing it outta yr garage etc.

They did remark that the ENGINE (as opposed to the suspension - see my other thread) is one of the most reliable in the range...