I've had my XC60 for just under a year now and it has been burning through about 1 liter of oil every couple of months depending on how hard I push it. If I go full "Miss Daisy" and keep the RPMs below 1500, the loss is about half as much. My initial assumption was that oil was pushing past one or more of the cylinder oil rings as this appears to be an issue with these engines. But I recently bought a OBD fault code reader and have the following three error codes, all related to turbo issues.
P023600 - Turbo/supercharger boost Sensor A circuit Range/performance - General defect Data - No Sub-type Data
P029900 - Turbo/supercharger A underbooost condition - General defect Date - No Sub-type Data
P004900 - Turbo/supercharger turbine overspeed - General defect Date - No Sub-type Data
I've had a look at what these things mean separately, but was hoping someone with a little more experience could come to a more specific diagnosis based on the existence off all three codes at the same time. The codes result in a noticeable loss of power, but not full limp mode. When cleared, the power issue goes away for a few days and then comes back.
Considering the heavy loss of oil, I am tempted to conclude that this is a turbo issue rather than an oil ring problem. The real question I'm trying to answer is how bad is the problem, how much will cost to set right, and is it worth spending that much money.
Any help would be greatly appreciated.