A P0306 diagnostic trouble code on your 2022 Lexus RX indicates a misfire detected on cylinder 6. The 2022 RX350 features a 3.5L V6 engine that produces 295 horsepower, and cylinder 6 is a valid component of this powertrain.
Understanding Your RX's Engine Layout
The 2022 RX350 uses Toyota/Lexus's proven 2GR-FKS 3.5L V6 with both port and direct fuel injection (D-4S). This dual injection system adds complexity to misfire diagnosis, as issues can stem from either injection system. Cylinder 6 is located at the rear of the right (passenger) bank.
Common Causes of P0306 in the 2022 RX
- Ignition Coil Failure: Direct ignition coils can fail without warning
- Spark Plug Wear: Iridium plugs may need replacement after 60,000 miles
- Direct Injector Issues: Carbon buildup or injector failure on the direct injection system
- Port Injector Problems: Less common but possible clogging or failure
- Intake Carbon Buildup: Direct injection engines can accumulate intake valve carbon deposits
- Vacuum Leaks: Intake manifold or gasket issues
Diagnostic Strategy
Start with the basics: retrieve all codes and review freeze frame data. Lexus's dual injection system means fuel delivery diagnosis requires attention to both injection systems. The coil-on-plug design makes component swapping straightforward for isolation testing.