Intake Camshaft Position Timing - Over-Advanced (Bank 2)

What is P0021?

P0021 indicates the intake camshaft on engine bank 2 is out of its proper timing position, being too far advanced. This is a powertrain issue of medium severity that affects engine performance and efficiency, and it is most commonly reported in the Nissan Maxima, Porsche Cayenne, and Ford Expedition. The code is typically triggered by problems within the variable valve timing system.

Common Causes

• ●Faulty variable valve timing (VVT) solenoid or oil control valve (seen in most cases)
• ●Low engine oil level or poor oil quality affecting VVT system pressure
• ●Worn timing chain or stretched timing components
• ●Faulty camshaft position sensor providing incorrect data to the ECU
• ●Issues with the engine's oil passages or clogged oil screens feeding the VVT actuator

Symptoms You May Notice

• ●Illuminated check engine light, often with reduced engine power
• ●Noticeable rough idle or engine misfires
• ●Poor fuel economy and reduced engine performance
• ●Engine may hesitate or stall during acceleration
• ●Audible rattling or ticking noises from the timing cover area at startup

How to Fix It

• ●Replace the variable valve timing (VVT) solenoid or oil control valve ($150-$400, moderate difficulty)
• ●Perform a full timing chain and component replacement, which is a major repair ($1000-$4000, high difficulty)
• ●Change engine oil and filter, and ensure proper oil level and quality ($50-$150, easy)
• ●Replace the camshaft position sensor ($100-$300, moderate difficulty)
• ●Clean or replace clogged oil screens and check oil passages in the VVT system ($200-$600, moderate difficulty)