Impreza WRX STI F4-2.5L Turbo (2008)
Valve Clearance: Adjustments
ADJUSTMENT
NOTE: Adjustment of valve clearance should be performed while engine is cold.
1) Measure all the valve clearances.
NOTE: Record each valve clearance after measurement.
2) Remove the camshaft.
3) Remove the valve lifter.
4) Measure the thickness of valve lifter using micrometer.
5) Select and install a valve lifter of suitable thickness from the following table, based on the measured valve clearance and valve lifter thickness.
NOTE: Use a new valve lifter.