Manifold Pressure Senso R; (Vacuum Sensor) - Toyota COMPUTER-CONTROLLED SYSTEM Training Manual

INSPECTION AND ADJUSTMENT - Manifold Pressure Sensor (Vacuum Sensor )
MANIFOLD PRESSURE SENSOR (VACUUM SENSOR)
OBJECTIVE
To learn the procedure for inspecting the manifold pressure sensor (vacuum
sensor) .
PREPARATIONS
.• Voltmeter ( also called "circuit tester" or "multi-tester")
• Mityvac ( hand-held vacuum pump )
APPLICABLE ENGINE : 4A-FE* (Sep ., 1989 )
*Except Carina
11 (AT
171) with lean mixture senso r
Vacuum chamber
E2
PIM
VC
~
From intake manifold
INSPECTION OF MANIFOLD PRESSURE SENSOR
(VACUUM SENSOR )
1 . CHECK POWER SOURCE VOLTAGE OF MANIFOLD
PRESSURE SENSO R
(a) Disconnect the manifold pressure sensor connector .
(b) Turn the ignition switch on .
(c) Using a voltmeter, measure the voltage between
terminals VC and E2 of the manifold pressure sensor
connector .
Voltage : 4 - 6 V
2 . CHECK POWER OUTPUT OF MANIFOLD PRESSURE
SENSO R
(a) Turn the ignition switch on .
(b) Disconnect the vacuum hose at the intake chamber
side .
(c) Connect a voltmeter to terminals PIM and E2 of the
ECU, and measure and record the output voltage
under the ambient atmospheric pressure .
(d) Using a Mityvac (hand-held vacuum pump), apply
vacuum to the manifold pressure sensor in
increments of 13 .3 kPa (100 mmHg, 3 .94 in .Hg) until
the vacuum reaches 66 .7 kPa (500 mmHg, 19 .69
in .Hg) .
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