Difference between Subaru and Audi though is for certain cars (09-11ish A4, A5, Q5) with the 2.0TSI engine, there is a class action warranty extension for oil consumption.
It is expiring in a few months but in a nut shell what happens is the customer complains the oil light is on or they have been adding oil (usually its like 1-2 quarts per 1k) And we do an oil consumption test. Audis have pretty accurate oil level sensors built into them so we can take measurements. Sometimes they want a weighed measurement but generally its a comparison for levels. So we get the car in and do whats called a phase 1. Top off the oil, run the oil consumption test plan with the scan tool and take a measurement. There is no dipstick on these cars so we take an actual digital measurement in mm.
Take that number, tell the customer to drive like 700 miles, come back, take another measurement and compare the two. Send those numbers to Audi and they tell us what to do. If all the testing was done correctly (the scan tool can tell and report if all requirements were met) it almost always ends with piston and ring replacement or an engine if the internals are found worn upon disassembly.
Yep, when we get an oil burner, we replace pistons and rings under warranty free of charge for the customer if Audi allows which is like 90% of the time.
For those who are curious, it pays 19-21 hours flat rate to do pistons and rings on an A4. And we have guys who can do it in 8 hours, no lie. Car comes in at 7:30 am and drives out with new pistons at 4 with a lunch break.
And yes. It fixes the problem. Once the pistons are done, they never come back with oil problems.