| Engine control module | |
| And emissions control system that prevents HC in missions from escaping the fuel system to atmosphere. | |
| The sprocket on the camshaft that is turned up by a chain or belt from the crankshaft. The camshaft sprocket has twice as many teeth as the cam shaft sprocket. | |
| The part of a battery made from two dissimilar metals and an acid solution. A cell stores chemical energy to be used later as electrical energy. |