The 2016 ATS is a sharp-handling compact luxury sedan undermined by the 2.0T engine's catastrophic timing chain and piston failures, plus transmission cooling issues across all powertrains. The 2.5L is more reliable but underwhelming; the 3.6L V6 is the best bet if you can find one.
2.0L Turbo Timing Chain Stretch and Engine Failure
Common · high severityTypical onset: 60,000-100,000 mi
Symptoms: Rattling noise on cold start that disappears after warm-up, Check engine light with timing correlation codes (P0017, P0018), Rough idle and reduced power, Complete engine failure if chain jumps timing
Fix: Timing chain replacement requires front engine teardown (12-16 hours). If chain has already jumped and bent valves, you're looking at head work or complete engine replacement (20-30 hours). Many owners opt for used/reman engines due to cost.
Estimated cost: $3,500-8,000
2.0L Turbo Piston Ring Failure and Carbon Buildup
Common · high severityTypical onset: 70,000-120,000 mi
Symptoms: Excessive oil consumption (1 quart per 1,000 miles or worse), Blue smoke from exhaust on startup or acceleration, Fouled spark plugs and misfires, Loss of compression
Fix: This is the death knell for the 2.0T. Piston rings fail due to carbon buildup on direct-injection engines. Proper fix is engine rebuild or replacement (25-35 hours). Some owners try walnut blasting and top-end cleaning, but it's temporary if rings are already damaged.
Estimated cost: $5,000-9,000
Transmission Oil Cooler Line Leaks
Common · medium severityTypical onset: 50,000-90,000 mi
Symptoms: Transmission fluid puddle under vehicle (red fluid), Low fluid warnings or harsh shifting, Fluid leaking near radiator or frame rail, Delayed engagement when cold
Fix: The cooler lines corrode where they run along the frame, especially in salt-belt states. Line replacement is straightforward but requires lifting the vehicle and sometimes removing undercarriage panels (3-5 hours including fluid flush).
Estimated cost: $600-1,200
CUE Infotainment System Failures
Occasional · low severitySymptoms: Touchscreen unresponsive or phantom touches, System freezes or reboots randomly, Climate controls inaccessible, Backup camera black screen
Fix: The CUE system is notoriously buggy. Software updates help temporarily. Many owners replace the entire CUE module (2-3 hours), though used units often have the same issues. Some opt for aftermarket head units but lose steering wheel controls.
Estimated cost: $800-2,500
Rear Transmission Mount Failure
Occasional · low severityTypical onset: 60,000-100,000 mi
Symptoms: Clunking when shifting from Park to Drive/Reverse, Excessive vibration under acceleration, Visible sagging or torn rubber on mount
Fix: The hydraulic rear transmission mount collapses over time. Replacement is accessible from underneath (1.5-2.5 hours). OEM parts are pricey but recommended over aftermarket.
Estimated cost: $400-700
Sunroof Drain Tube Clogs and Water Leaks
Occasional · medium severitySymptoms: Water dripping from headliner onto seats, Wet carpets in footwells (especially front passenger), Musty smell in cabin, Electrical issues if water reaches modules
Fix: Drain tubes clog with debris and back up into the cabin. Clearing tubes requires removing A-pillar trim and sometimes headliner (2-4 hours). If water has damaged modules or carpets, repair cost escalates quickly.
Estimated cost: $300-1,500
Pass on the 2.0T unless you're getting it cheap enough to budget for an engine replacement; the 3.6L V6 is worth seeking out, but even then, expect typical GM electronics headaches and transmission cooling issues.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.