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486 PL ENGINE
P
SENSORS IN MOTRONIC SYSTEM
a) Hot film mass air flow sensor (HFM)
It measures the mass flow of air entering into
the inlet manifold. Fig. 6
b) Coolant temperature sensor
Fig. 7
It detects the coolant temperature and transmits
electrical signal to the ECU. It is mounted in
the water jacket of the engine on cylinder head.
c) Knock sensor
Fig. 8
It detects the occurrence of the knock and
signals it to the ECU. It consists of a peizo
ceramic element. There are two knock sensors
for four cylinders. The ECU retards the ignition
timing by specific values thereby controlling
the knock, if it occurs.
d) Engine speed sensor
Fig. 9
It senses the engine speed. It picks up signals
from sensor wheel mounted on the crankshaft.
It is mounted on the cylinder block on left hand
front side of the engine.
Fig. 7
Fig. 8
Fig. 9
Fig. 6
KNOCKSENSORS
ENGINE SPEED
SENSOR