| Exhaust gas recirculation valve | |
| To cool a vapor to below its boiling point, where it then condenses into a liquid. | |
| A cylindrical hole. | |
| Enclosure formed by a pocket in the cylinder head at the top of the piston, where the spark plug ignites the compressed air/fuel mixture. The volume of the cylinder above the piston when the piston is at TDC top dead center. |