Very high oil consumption on 2nd hand car Vs. Sales of Goods Act 1979

colino

Trying to stay factual here, the engine does appear to have gained notoriety as being heavy on oil consumption.
No one knows yet if this engine is burning it leaking it or has a failed sensor.

vaio

Factual is good but I'm sure the OP would have mentioned the mess that a 1l/1000miles leak would make, after 1500+ miles there would be a 1.5l of oil over the engine/drive. I'm struggling to think of a sensor that could cause oil loss/burn.

I suppose the oil level measuring sensor could have failed but I'd have thought it either wouldn't work at all or would give the same reading all the time, a failure that mimicked oil loss seems unlikely.

colino

Well done with your remote diagnosis (with absolutely no information in front of you other than an owner complaining of excessive oil consumption).
Many engines can and do leak when they are running, negligible drips when stopped.
Measuring devices on cars are pretty dumb pieces of kit, they act within the range they have been built to and the subsequent driver interface; guage, dial or idiot light, accordingly. How accurate is your fuel guage, coolant temperature guage or speedo?
Go on then, what's the fault and what is the cure?


Thought not.

vaio

Thanks, remote diagnosis is fun

Even with the limited information we have I am sure that the OP would have noticed if 1.5 litres of oil had leaked out over the space of 18 days.

I've never checked how accurate my gauges are...they tell me I'm low, I top up, they tell me the new level then later they tell me I'm low again etc. They do go wrong but as above, they either stop working or give the same reading all the time. I struggle to think of a failure mode where a gauge would mimic fluid loss on a repeated basis if the fluid wasn't actually disappearing..

As to what's wrong, can't be sure obviously but give the widely reported problems Audi are having on the <2011 TFSI family of engines I'd certainly be leaning towards ring/bore issues. Audi tech document 2026749/8 (fit new pistons/rings/conrods) refers

IamNotAllowedToUseMyName

I used to have a measuring system on my Merc. You need to be aware of what temperature the engine is supposed to be at, whether the ground is level and so on (Merc required warm engine then stood for 5 minutes to allow oil to settle). I don't know how accurate such a gauge is, on the Merc it read zero, -0.5l and -1.0l and insisted on topping up at -1.5l. Clearly though it could be 0.25l down and not confess.

So we don't know whether the oil was spot on at the start, or an approximate measure. So the OP has come up with an accurate sounding figure based on one reading when we don't really know the accuracy of the first or second reading. It is quite possible that the oil level was not correct in the first place and the second reading was not done accurately.

What I would do in this situation is call the garage to say that I have just had to put a substantial amount of oil in the engine based on the gauge and you are concerned. I would then see if they invited me in to check (ah, sir, it is a known problem and we have a fix) or alternatively say that I will be monitoring it because it is just a single reading and if the consumption is confirmed to be excessive in the next 1000 miles I will be bringing it back in for a fix.

What warranty did you get?

almillar

I wondered when the usual 'man in the pub' BS would pop up about rotary engines lol. The RX8 uses about .25l per 1000 miles*. A lot less than an Audi it seems.

* More if you drive it hard

Yup, but the difference is that all other cars it's a 'tolerance' whereas the RX8 actually purposely puts the oil into the engine. Really not a big deal at all in my experience to check the oil and top it up the odd time. You're meant to do this with all cars. With so many turbo engines around it's going to become a bigger problem, with people used to engines that don't burn any oil having a dry engine. Turbos can burn oil, keep checking!