Engine Speed Sensor

The Engine Speed Sensor (ESS) is mounted on the front engine cover, near crankshaft pulley. A toothed pulse wheel is mounted on the front of the crankshaft gear, causing an electronic pulses in the ESS with each engine revolution. These pulses are converted into an electrical signal which is sent to the MCU. The MCU uses this information to determine engine RPM. A missing tooth creates a gap in the signal, which is used to determine engine position.