2003 Infiniti G35 P0300 and P0021 Fault: VVT Solenoid Replacement or Engine Internal Issue?
My 2003 Infiniti G35 is showing fault codes P0300 (Random Misfire) and P0021 (Variable Valve Timing - VVT Position Sensor Circuit). Using an AutoZone code reader, I've confirmed these codes. I'm considering testing the VVT solenoid (Part Number Dorman 917-012) while it's still installed in the engine. If the test shows a faulty reading, will replacing the solenoid resolve the issue? Or is it more likely that the problem lies inside the engine—such as the camshaft timing gear or internal valve train components? Any guidance on diagnostics or next steps would be greatly appreciated.
Before removing the VVT solenoid, it's recommended to test its resistance with a multimeter while the engine is off (KOEO). The expected resistance should be between 7.0 and 7.5 ohms at 20°C (60°F). This basic check can help determine if the solenoid is faulty without disassembly.