Camshaft Operation:

A shaft having lobes driven by the crankshaft via gears, chains, or belts that, in turn, opens and closes the intake and exhaust valves at proper intervals.
How To Instructions:
Inspect
- Check for obvious problems.
Test
- Give it an in-depth diagnosis.
Service
- Do the jobs that fix your car.
Replace
- Out with the old, in with the new.