DTC P0021 Intake Camshaft Position - Timing Over-Advanced Or System Performance (Bank 2): Trouble Symptom

WARNING: This page is about a different car, the 2012 Subaru Forester. However, it is still accessible from the selected car via links, so may be relevant.

Engine stalls.
Improper idling

CAUTION: After servicing or replacing faulty parts, perform Clear Memory Mode < refer to OPERATION , Clear Memory Mode. >, and Inspection Mode < refer to PROCEDURE , Inspection Mode. >.

DIAGNOSIS PROCEDURE

Step	Check	Yes	No
1 CHECK CURRENT DATA. Start the engine and let it idle. Check the AVCS system operating angle using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". < refer to SUBARU SELECT MONITOR . > General scan tool For detailed operation procedures, refer to the general scan tool operation manual.	Is the AVCS system operating angle approximately 0°?	Go to step 2.	Check the following item and repair or replace if necessary. Intake cam sprocket (clog or dirt of oil routing, setting of spring) Intake camshaft (dirt, damage of camshaft)
2 CHECK CURRENT DATA. Drive with acceleration and deceleration at 80 km/h (50 MPH) or less. NOTE: Drive to an extent that the duty output of oil control solenoid increases. Measure the AVCS system operating angle and oil control solenoid duty output using Subaru Select Monitor or general scan tool. NOTE: Subaru Select Monitor For detailed operation procedures, refer to "READ CURRENT DATA FOR ENGINE". < refer to SUBARU SELECT MONITOR . > General scan tool For detailed operation procedures, refer to the general scan tool operation manual.	When the oil control solenoid duty output exceeds 10%, is the AVCS system operating angle approx. 0°?	Check the following item and repair or replace if necessary. Intake cam sprocket (clog or dirt of oil routing, setting of spring) Intake camshaft (dirt, damage of camshaft)	Perform the following procedures, and clean the oil routing. Replace the engine oil and idle the engine for 5 minutes, and then replace the oil filter and engine oil. < refer to REPLACEMENT , Engine Oil. > < refer to ENGINE OIL FILTER . >