2002 Nissan Maxima P0021 Code: Recurring SES Light After Camshaft Timing Repair
A little over a month ago, my 2002 Nissan Maxima's Service Engine Soon (SES) light activated with fault code P0021. Shortly after, the vehicle stalled on the highway. I took it to the dealership, where they replaced the Camshaft Position Sensor and two gaskets. However, less than two months later, the SES light came back on with the same P0021 code. The dealer now wants to perform another inspection. Given that this is a recurring issue, what should I know about P0021 in my 2002 Maxima? Are there common underlying causes or signs I might be missing?
P0021 relates to the intake valve timing control system, which is electrically driven (not hydraulic via oil pressure). Below are potential causes to consider: > Harness or connectors — possible open or short circuit in the intake valve timing solenoid valve circuit. > Intake valve timing control solenoid valve itself — could be faulty or malfunctioning. > Crankshaft Position Sensor (POS) — inaccurate readings may trigger P0021. > Camshaft Position Sensor (PHASE) — improper signal can lead to incorrect timing interpretation. > Debris buildup on the camshaft pickup sensor — especially in older engines, this can interfere with signal accuracy. * Engine oil level, quality, and pressure also play a significant role in proper camshaft timing operation.