2007 GTI 6MT 110k miles. Normally this car burns about a quart ever 1k miles but lately (within the last 4 months or so) it's closer to 250-500 miles. It could be leaking but I haven't noticed any drips on the ground. I've also noticed changes in the the boost from being smooth all the way from idle to redline to being, most recently erratic, lumpy boost from about beyond 3500 RPM. Sometimes the boost is smooth to red line, sometimes it's erratic, there isn't much consistency. Lately it's been more and more erratic. Every now and then if I increase throttle input during the lumpy phase it will either blow a fair amount of smoke out of the tailpipe and or make a metal fluttering sound and appears to lose all boost pressure (right in the 3-5k range). Because of the oil burning and the above symptoms, I've been driving it like a grandma lately but I'd like to get it checked out but was wondering if I could trouble shoot it first. I have a VAGCOM so I can try to make some boost logs but I don't if it will help much. I ran an autoscan and there are no relevant faults. Things I'm thinking it could be: PCV - most recently, I've heard a high pitched whistle sound DV Valve cover gasket Bad turbo seals Piston rings I will likely take the car to Black Forest but what should I start with? Compression test? Just have them replace the PCV and DV while they're at it and see if that fixes it? Any thing I can check with VCDS. Boost log?