>> E << O-Ring Installation
WARNING: This page is about a different car, the 2014 Mitsubishi Outlander. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
Do not allow engine oil to enter the fuel rail.
When inserting an O-ring into the injector on the injection nozzle side, use special tool O-ring installer (MB992106) to gradually expand the O-ring, and fit it in place.