THINK TWICE

The BMW N20 2.0T's defining failure is timing-chain wear -- the chain guides and tensioner -- that can destroy the engine. On the 2.0-liter turbo four (the 328i 2012-2016, X3 xDrive28i 2013-2017 and 528i 2012-2016) the plastic-toothed guides and the tensioner wear out and the chain can stretch, skip or snap; because the engine is an interference design the valves then meet the pistons and the engine is finished. Owners describe it the same way over and over in federal complaints: a drivetrain-malfunction warning and limp mode, then a sudden shutdown and a tow, and a quote to rebuild or replace the engine (one 2013 X3 owner: "the N20 timing chain ... Engine blows if not fixed immediately"; another: "sudden and complete engine failure without warning"). It is the dominant engine complaint on these cars and it does not wait for high mileage -- reports run from the low tens of thousands of miles to past 100k. BMW addressed it through a warranty extension / class action rather than a federal recall, so there is no campaign to VIN-check.

Check — Ask whether the timing chain, guides and tensioner have been replaced with the updated parts and get documentation. A rattle from the front of the engine on a cold start, a drivetrain-malfunction message, or any limp-mode history are warnings -- as is neglected oil service, which accelerates guide wear. On an N20 with no chain history budget for the job (often four figures) or walk away; a skipped chain means a new engine. Confirm the car is actually the N20 turbo four, not the N55 six (335i/535i) or the older naturally-aspirated N52.