Mitsubishi Evolution X. Manual - part 122

SENSOR

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MULTIPORT FUEL SYSTEM (MFI)

13A-17

The intake camshaft position sensor uses a magnetic resis-
tance element. When the camshaft position sensing portion
passes the front surface of the magnetic resistance element,
the flux from the magnet passes the magnetic resistance ele-
ment. Thus, resistance of the magnetic resistance element
increases. When the camshaft position sensing portion does
not pass the front surface of the magnetic resistance element,
the flux from the magnet does not pass the magnetic resistance
element and the resistance decreases. The intake camshaft
position sensor converts this change in resistance of the mag-
netic resistance element to a 5 V pulse signal and outputs it to
ECM.

EXHAUST CAMSHAFT POSITION SENSOR

The exhaust camshaft position sensor is installed on the
exhaust side of the cylinder head. The exhaust camshaft posi-
tion sensor monitors shape of the half-moon sensing portion
and converts to voltage (pulse signal) that is output to ECM.
Upon receiving this output voltage, the ECM effects feedback
control to optimize the phase of the exhaust camshaft. The
structure and system of this sensor are basically the same as
intake camshaft position sensor.

AK702327AD

Camshaft position sensing portion

Magnetic resistance element

Magnet flux

AK602287

5 V

Intake camshaft position sensor

ECM

Output signal

Magnetic resistance element

SENSOR

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MULTIPORT FUEL SYSTEM (MFI)

13A-18

KNOCK SENSOR

A knock sensor is installed on the intake side of the cylinder
block. Knock sensor uses the piezoelectric element to convert
the vibration of the cylinder block generated when engine is in
operation to minute voltage that is output to ECM. ECM uses
the minute output voltage from the knock sensor filtered
through the cylinder block's natural frequency to detect knock-
ing, and compensates the ignition timing lag according to the
strength of the knocking.

AK602287

5 V

Exhaust camshaft position sensor

ECM

Output signal

Magnetic resistance element

AK604903AD

Piezoelectric element

AK602226

Knock sensor

Piezoelectric element

ECM

SENSOR

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MULTIPORT FUEL SYSTEM (MFI)

13A-19

BAROMETRIC PRESSURE SENSOR

A barometric pressure sensor is built into ECM. The barometric
pressure sensor is a semiconductor diffused pressure element
which outputs voltage to ECM according to atmospheric pres-
sure. ECM uses this output voltage to sense the altitude of the
vehicle and compensates fuel injection volume to achieve the
appropriate air-fuel ratio for that altitude.

ENGINE OIL PRESSURE SWITCH

The engine oil pressure switch is installed on the intake side of
the cylinder block. The engine oil pressure switch detects
whether the oil pressure is high or low using the contact switch.
When the oil pressure becomes higher than the specified value
after the engine starts, the contact point of the engine oil pres-
sure switch opens. This allows the ECM to detect the oil pres-
sure is higher than the specified value. The ECM outputs the
OFF signal to the combination meter through the CAN and then
turns off the oil pressure warning lamp.

AK602575AC

Barometric pressure sensor
(built in ECM)

AK602587AC

Oil
pressure

Contact switch

AK602228

OFF

ECM terminal voltage V

Oil pressure:low

Oil pressure: high

Operating pressure

Oil pressure kPa (in.Hg)

Engine oil
pressure switch

ECM

SENSOR

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MULTIPORT FUEL SYSTEM (MFI)

13A-20

POWER STEERING PRESSURE SWITCH

A power steering pressure switch is installed on the power
steering oil pump. The power steering pressure switch uses a
contact switch to detect the power steering pressure. When
power steering pressure rises due to operation of the steering
wheel, the power steering pressure switch outputs an ON sig-
nal to ECM. ECM performs idle-up according to the voltage and
prevents reduction in engine speed due to power steering load
and so maintains stable idle speed.

CLUTCH PEDAL POSITION SWITCH <M/T>

Clutch pedal position switch is installed on the clutch pedal.
Clutch pedal position switch uses a contact switch that detects
whether or not a pedal effort is applied to the clutch pedal.
Upon detecting a pedal effort applied to the clutch pedal, the
ECM effects control to retard the ignition timing.

AK702847AD

Power steering
pressure switch

Oil
pressure

AK602213

OFF

Oil pressure:low

Oil pressure: high

Operating pressure

Power steering
pressure switch

OFF

ECM

ECM
terminal voltage V

Oil pressure kPa (in.Hg)

AK702848

Clutch pedal
position switch

Clutch interlock switch

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