Side Clearance
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.
Measure the gap between the inner rotor and the oil pump case to measure the clearance between the inner rotor and the oil pump cover as shown in the figure. If clearance is out of standard, replace the rotor or the oil pump case.
Side clearance between inner rotor and pump case:
Standard
0.02 - 0.07 mm (0.0008 - 0.0028 in)