the automobile

10. opens and closes the intake and exhaust valves of the engine cylinder head
12. used to engage or disengage the engine and transmission
13. uses an internal hydraulic system to shift gears
15. contains a differential and two axles.
16. the part of a piston engine which connects the piston to the crankshaft
19. these return the valves to there seated position when there is no pressure applied
20. a mechanical component used in a piston engine to convert the reciprocating motion into rotational motion

1. produces extremely high voltage that operates the spark plugs
2. allows the driver to change gear ratios and engine torque going to drive wheels
3. reduces friction and wear between internal engine parts
4. transfers turning force from the engine crankshaft to the drive wheels
5. are mechanically opened and closed, to admit air or expel exhaust gasses, into the engine cylinder(s)
6. contains a transmission and a differential in one case
7. these are mounted between the engine block and intake manifold
8. these are used to open the valves for fuel and exhaust
9. sits between a car's camshaft and the cylinder valves
11. used inside the engine for compression connected to the crankshaft
14. the main body of an internal combustion engine containing the pistons
17. replaces electrical energy used during the starting system operation
18. transfers power from the transmission to the rear axle assembly