AVCS Exhaust LH Oil Control Valve Solenoid

The AVCS exhaust oil control valve is responsible for the oil flow to the variable cam timing sprocket.  This part is an assembly with the holder (mounting block) and solenoid and is for the left hand side.  A filter inside the holder prevents debris from reaching the cam sprocket.  For this reason this part should always be replaced when rebuilding after a bearing failure or any other failure that leads to extensive metal debris in the oil system.  A faulty solenoid or clogged passage can cause a CEL to set related to the exhaust AVCS system.  

The AVCS (Active Valve Control System) is used by Subaru to vary the camshaft timing in order to improve efficiency and reduce emissions across the rpm range.  Dual AVCS models use this system on both the intake and exhaust cams.  The system, under control of the ECU, uses cam sprockets with a center hub that can rotate within a fixed number of degrees relative to the outer portion driven by the timing belt.  The AVCS oil control valves (solenoids) control the direction of oil flow into and out of a series of chambers inside the sprocket in order to advance or retard the timing as necessary.  This system has parts with very tight tolerances and small metal debris can affect proper operation.

Manufacturer Part No.: 10917AA070

What it fits:

• EJ257 MY08-21
• EJ207 MY08-20
• EJ20X/EJ20Y