| Passage or opening in a four stroke cylinder head for the exhaust valve. | |
| A fuel injection system wherein fuel is sprayed directly into the combustion chamber, that is, no precombustion chambers or manifold injection. | |
| A device used with disc brake pads to help them from moving and making noise. | |
| A climate control system that uses the heating and air-conditioning system to maintain that interior temperature selected by the vehicles passengers. |