Intake/Exhaust Valves & Seats: Operation
WARNING: This page is about a different car, the 2005 Dodge Stratus and 2005 Chrysler Sebring. However, it is still accessible from the selected car via links, so may be relevant.
The four valves per cylinder (two intake and two exhaust) are opened by using roller camshaft followers which pivot on hydraulic lash adjusters.