Page 369 of 656
6E2-36 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
Engine coolant temperature sensor (ECT sensor)
REMOVAL
1) Disconnect negative (–) cable from battery.
2) Drain cooling system.
3) Disconnect coupler from ECT sensor (1).
4) Remove ECT sensor from water outlet cap (2).
INSPECTION
Immerse temperature sensing part of ECT sensor in water and
measure resistance between sensor terminals while heating
water gradually.
If measured resistance doesn’t shown such characteristic as
shown in the figure, replace ECT sensor.
INSTALLATION
Reverse removal procedure noting the followings.
•Clean mating surfaces of sensor and water outlet cap (1).
•Use new O-ring.
•Tighten ECT sensor to specified torque.
Tightening torque
ECT sensor (a) : 15 N·m (1.5 kg-m, 11.0 lb-ft)
•Connect coupler to sensor securely.
•Refill cooling system.
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ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-37
Heated oxygen sensor (sensor 1)
REMOVAL
1) Disconnect negative (–) cable from battery.
2) Disconnect coupler of oxygen sensor (s).
3) Remove oxygen sensor (s) from exhaust manifold (s).
INSTALLATION
Reverse removal procedure noting the followings.
•Tighten oxygen sensor (s) to specified torque.
Tightening torque
Heated oxygen sensor 1
(a) : 45 N·m (4.5 kg-m, 32.5 lb-ft)
•Connect connector of oxygen sensor (s) and clamp wire har-
ness securely.
•After installing oxygen sensor (s), start engine and check
that no exhaust gas leakage exists.
INSPECTION
Inspect HO2S-1 and its circuit referring to “DTC P0130 or P0150
Diag. Flow Table” in Section 6-1. If malfunction is found, replace. WARNING:
To avoid danger of being burned, do not touch exhaust
system when system is hot. Oxygen sensor removal
should be performed when system is cool.
NOTE:
Be careful not to expose it to excessive shock.
1. Left (No.1) bank oxygen sensor (sensor 1)
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6E2-38 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
HEATER INSPECTION
1) Disconnect HO2S-1 or -2 coupler.
2) Using ohmmeter, measure resistance between terminals
“VB” and “GND” of HO2S coupler (1).
If found faulty, replace HO2S.
Resistance of HO2S heater:
11.7 – 14.3 Ω
ΩΩ Ω (at 20 °C (68 °F)) for HO2S-2
5.0 – 6.4 Ω
ΩΩ Ω (at 20 °C (68 °F)) for HO2S-1
3) Connect HO2S coupler securely.
Heated oxygen sensor (sensor 2)
REMOVAL
1) Disconnect negative (–) cable from battery.
2) Disconnect coupler (3) of oxygen sensor(s).
3) Remove oxygen sensor(s) (2) from exhaust manifold(s) (1).
INSTALLATION
Reverse removal procedure noting the followings.
•Tighten oxygen sensor(s) to specified torque.
Tightening torque
Heated oxygen sensor 2 (a) : 45 N·m (4.5 kg-m, 32.5 lb-ft)
•Connect connector of oxygen sensor(s) and clamp wire har-
ness securely.
•After installing oxygen sensor(s), start engine and check that
no exhaust gas leakage exists. NOTE:
Temperature of HO2S affects resistance value largely.
Make sure that HO2S heater is at correct temperature.
WARNING:
To avoid danger of being burned, do not touch exhaust
system when system is hot. Oxygen sensor removal
should be performed when system is cool.
NOTE:
Be careful not to expose it to excessive shock.
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ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-39
HEATER INSPECTION
Refer to “HEATED OXYGEN SENSOR (SENSOR 1) HEATER
INSPECTION”
Vehicle speed sensor (VSS)
ON-VEHICLE INSPECTION
1) Hoist vehicle.
2) Release parking brake lever, set transmission in neutral and
transfer in “2H”.
3) Remove ECM (PCM) cover.
4) Connector voltmeter between VSS terminal C51-3-1 of ECM
(PCM) connector and body ground.
5) Turn ignition switch ON and turn rear right tire slowly with
rear left tire locked.
Voltmeter should indicate deflection between 0 – 1 V and 8 –
14 V a few times while tire (1) is turned one revolution.
If check result is not satisfactory, proceed to flow table of
“DTC P0500” in Section 6-1.
REMOVAL, INSPECTION AND INSTALLATION
Refer to “VSS Removal, Inspection or Installation” in Section 7D.
Manifold absolute pressure sensor
REMOVAL
1) Disconnect negative (–) cable at battery.
2) Disconnect connector from manifold absolute pressure sen-
sor.
3) Remove manifold absolute pressure sensor from intake
manifold.
[A]: Terminal arrangement of ECM (PCM) coupler
(viewed from harness side)
1. VSS
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6E2-40 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
INSPECTION
1) Check sensor O-ring (1) for damage and deterioration.
Replace as necessary.
2) Arrange 3 new 1.5 V batteries (2) in series and connect its
positive terminal to “Vin” terminal of MAP sensor (1) and
negative terminal to “Ground” terminal. Then check voltage
between “Vout” and “Ground”.
Also, check if voltage reduces when vacuum is slowly
applied up to 400 mmHg by using vacuum pump (3).
If check result is not satisfactory, replace manifold absolute
pressure sensor.
MAP sensor output voltage (Vin voltage 4.5 – 5.5 V, ambi-
ent temp. 20 – 30°C (68 – 86°F))
CAUTION:
As connection to wrong terminal will cause damage to
manifold absolute pressure sensor, make absolutely sure
to connect properly as shown in the figure.
ALTITUDE
(Reference)BAROMETRIC
PRESSUREOUTPUT
VOLTAGE
(ft) (m) (mmHg) (kPa) (V)
0
–
20000
–
610760
–
707100 – 94 3.3 – 4.3
2001
–
5000611
–
1524Under 707
over 63494 – 85 3.0 – 4.1
5001
–
80001525
–
2438Under 634
over 56785 – 76 2.7 – 3.7
8001
–
100002439
–
3048Under 567
over 52676 – 70 2.5 – 3.3
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ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-41
INSTALLATION
1) Confirm that vacuum passage on intake manifold is free from
clog.
2) Apply engine oil to O-ring of sensor.
3) Install sensor (1) to intake manifold (2).
4) Connect connector to sensor (1) securely.
Fuel level sensor (sender gauge)
Refer to Section 8C.
Crankshaft position sensor
REMOVAL AND INSTALLATION
Refer to Section 6A4.
INSPECTION
Refer to Section 6-1.
Main relay
INSPECTION
1) Disconnect negative (–) cable at battery.
2) Remove main relay (1) from its connector.
2. Fuel pump relay
3. Fuse box
4. Instrument panel
[A]: Left-hand steering vehicle
[B]: Right-hand steering vehicle
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6E2-42 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
3) Check resistance between each two terminals as in table
below.
If check results are as specified, proceed to next operation
check. If not, replace.
Main relay resistance:
4) Check that there is continuity between terminals “A” and “B”
when battery is connected to terminals “C” and “D”.
If malfunction is found, replace.
Fuel pump relay
INSPECTION
1) Disconnect negative (–) cable at battery.
2) Remove fuel pump relay (2) from connector.
3) Structure of fuel pump relay is the same as that of main
relay.
Check its resistance and operation using the same proce-
dure as that for main relay.
If malfunction is found, replace. TERMINALS RESISTANCE
Between “A” and “B”∞
∞∞ ∞ (Infinity)
Between “C” and “D”
79 – 95 Ω
ΩΩ Ω (at 20
°C (68°F))
1. Main relay
3. Fuse box
4. Instrument panel
[A]: Left-hand steering vehicle
[B]: Right-hand steering vehicle
Page 376 of 656
ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-43
Fuel cut operation
INSPECTION
1) Warm up engine to normal operating temperature.
2) While listening to sound of injector by using sound scope (1)
or such, increase engine speed to higher than 3,000 r/min.
3) Check to make sure that sound to indicate operation of injec-
tor stops when throttle valve is closed instantly and it is
heard again when engine speed is reduced to less than
about 2,000 r/min. NOTE:
Before inspection, check to make sure that gear shift
lever is in Neutral position (with A/T model, selector lever
in “P” range) and that parking brake lever is pulled all the
way up.