The Q5 lineup we see most is the 2.0T (EA888 Gen 2 and Gen 3) and 3.0T supercharged. Each has its own CEL signature: Gen 2 throws timing chain codes (P0016, P0017) when the tensioner fails, Gen 3 throws lean codes from PCV diaphragm cracks, and the 3.0T throws misfires from water pump coolant intrusion into spark plug tubes.
Engine & Platform Notes
- EA888 Gen 2 (2009–2012): chain tensioner is the #1 timing fault
- EA888 Gen 3 (2013+): PCV and carbon — borescope before recommending walnut blast
- 3.0T supercharged: water pump leaks coolant into the valley — check spark plug tubes for coolant