| A voltage signal that uses on off pulses. | |
| A magnetic, hall effect, optical or magneto resistive sensor usually mounted internally in the engine, externally to the engine are in the distributor to inform the ECM or PCM of the crankshaft position location of No. 1 piston, and crankshaft speed for ignition timing and other calculationneeded by the system where RPM is in input. | |
| Department of transportation | |
| The temperature to which the liquid turns to vapor. |