The P0303 diagnostic trouble code on your 2024 Cadillac XT6 indicates the powertrain control module has detected consistent misfires in cylinder 3. The 2024 XT6 continues with the refined 3.6L V6 powertrain.
2024 XT6 Engine Details
The 2024 XT6's LGX 3.6L V6 produces 310 horsepower with direct fuel injection. Cylinder 3 is at the rear of the driver's side bank. This proven engine benefits from continuous refinement.
Typical Causes
- Ignition Coil Problems: Coil-on-plug failures from heat and age
- Spark Plug Condition: Iridium plugs wear over time
- Fuel Injector Issues: Direct injection deposits
- Carbon Deposits: GDI valve accumulation
- Intake System Leaks: Manifold or gasket failures
Diagnostic Process
Use GM diagnostic equipment for detailed access. Monitor misfire counts and fuel trim values. Test ignition components through swap testing. Check for applicable TSBs.
Repair Recommendations
Replace faulty ignition coils with AC Delco parts. Install GM-specified spark plugs. Address fuel injector cleaning as needed. Dealer service ensures warranty coverage.