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ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-17
Idle mixture inspection/adjustment (vehicle without
heated oxygen sensor)
All vehicles not equipped with heated oxygen sensor are shipped
with their CO % factory adjusted as follows.
Engine idle mixture (CO %)
0.8 – 1.3 % at specified idle speed
Idle mixture adjustment should never be changed from the origi-
nal factory setting. However, if during diagnosis, the check indi-
cates idle mixture to be the cause of a driver performance
complaint or emission failure, the idle mixture can be adjusted
using the following procedures.
1) Check idle speed according to “Idle Speed/Idle Air Control
Duty Inspection” in this section.
2) Using exhaust gas tester, check that idle mixture CO % is
within above specification. If it is out of specification, adjust it
to specification by turning resistor knob (1).
3) If idle mixture has been adjusted, confirm that idle speed is
within specification. NOTE:
For this inspection and adjustment, exhaust gas tester
(CO meter) and engine tachometer are necessary.
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ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-21
14) Install strut tower bar (1) and tighten bolts.
15) Refill cooling system.
16) Connect negative (–) cable at battery.
17) Adjust accelerator cable and A/T throttle cable, refer to
“ACCELERATOR CABLE ADJUSTMENT” and “A/T THROT-
TLE CABLE ADJUSTMENT” in this section.
Idle air control valve (IAC valve)
REMOVAL
1) Disconnect negative (–) cable at battery.
2) Disconnect IAC valve connector.
3) Remove IAC valve (1) from throttle body.
INSPECTION
1) Disconnect connector from IAC valve.
2) Check each coil of IAC valve for resistance.
If resistances is out of specification, replace.
IAC valve resistance:
Terminals Resistance
Between “1” and “2”
25.5 - 33.5 Ω
ΩΩ Ω Between “3” and “2”
Between “4” and “5”
Between “6” and “5”
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6E2-22 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
3) Remove air cleaner outlet hose and remove IAC valve from
throttle body.
4) Connect connector to IAC valve.
5) Check that plunger (1) of IAC valve moves once and then
stops as soon as ignition switch (2) is turned OFF after
cranking engine for 2 sec.
If plunger (1) of IAC valve does not operate at all, check wire
harnesses for open and short. If wire harnesses are in good
condition, replace IAC valve and recheck.
INSTALLATION
1) Install new O-ring to throttle body.
2) Install IAC valve to throttle body.
3) Tighten IAC valve screws to specified torque.
Tightening torque
IAC valve screw (a) : 3.5N·m (0.35 kg-m, 2.5 lb-ft)
4) Connect IAC valve connector securely.
5) Connect negative (–) cable to battery.
Fast idle air valve
1) Disconnect IAC valve coupler with ignition switch OFF.
2) Check that with cold engine started, as cooling water tem-
perature rises, engine idle speed reduces gradually.
If check result is as described above, fast idle air valve is in
good condition.
If not, fast idle air valve, air passage or coolant passage is
faulty. NOTE:
This check should be performed by two people, one per-
son operates ignition switch while the other checks
plunger operation.
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ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-23
Fuel Delivery System
Fuel pressure inspection
1) Relieve fuel pressure in fuel feed line referring to “FUEL
PRESSURE RELIEF PROCEDURE” in Section 6-1.
2) Disconnect fuel feed hose from (3) delivery fuel feed pipe (1).
3) Connect special tools and hose (2) between fuel feed hose
and fuel feed pipe as shown in figure, and clamp hose
securely to ensure no leaks occur during checking.
Special tool
(A) : 09912-58441
(B) : 09912-58431
(C) : 09912-58490
4) Check that battery voltage is above 11 V.
5) Turn ignition switch ON to operate fuel pump and after 3 sec-
onds turn it OFF. Repeat this 3 or 4 times and then check
fuel pressure.
6) Start engine.
7) Measure fuel pressure at idling.
If measure pressure doesn’t satisfy specification, refer to
“Diagnostic Flow Table B-3” in Section 6-1 and check each
possibly defective part. Replace if found defective.
Fuel pressure specification: CAUTION:
A small amount of fuel may be released when fuel feed
hose is removed. Place container under the fuel feed
hose or fuel feed pipe with a shop cloth so that released
fuel is caught in container or absorbed in cloth. Place
that cloth in an approved container.
CONDITION FUEL PRESSURE
With fuel pump operating and
engine stopped270 – 310 kPa
2.7 – 3.1 kg/cm
2
38.4 – 44.0 psi
At specified idle speed 210 – 260 kPa
2.1 – 2.6 kg/cm
2
29.8 – 37.0 psi
With 1 min. after engine (fuel pump)
stop (Pressure reduces as time
passes)over 200 kPa
2.0 kg cm
2
28.4 psi
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6E2-24 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
8) After checking fuel pressure, remove fuel pressure gauge
(1).
9) Remove fuel pressure gauge, hose and 3-way joint.
10) Connect fuel feed hose and clamp it securely.
11) With engine “OFF” and ignition switch “ON”, check for fuel
leaks.
Fuel pump
ON-VEHICLE INSPECTION
1) Remove filler cap and turn ON ignition switch (2). Then fuel
pump operating sound should be heard from fuel filler (1) for
about 3 seconds and stop. Be sure to reinstall fuel filler cap
after checking.
If above check result is not satisfactory, advance to “DIAG-
NOSTIC FLOW TABLE B-1” in Section 6-1
2) Fuel pressure should be felt at fuel return hose (1) for 3 sec-
onds after ignition switch ON.
If fuel pressure is not felt, advance to “DIAGNOSTIC FLOW
TABLE B-3” in Section 6-1. CAUTION:
As fuel feed line is still under high fuel pressure, make
sure to release fuel pressure according to following pro-
cedures.
Place fuel container under joint.
Cover joint with rag and loosen joint nut slowly to
release fuel pressure gradually.
CAUTION:
When fuel filler cap is removed in any procedure, work
must be done in a well-ventilated area, keep away from
any open flames and without smoking.
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ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-25
REMOVAL
Remove fuel tank from body according to procedure described in
Section 6C and remove fuel pump from fuel tank.
INSPECTION
Check fuel pump filter for evidence of dirt and contamination. If
present, clean and check for presence of dirt in fuel tank.
INSTALLATION
Install fuel pump to fuel tank and then install fuel tank to body
according to procedure described in “Section 6C”.
Fuel pressure regulator
REMOVAL
1) Relieve fuel pressure in fuel feed line referring to “FUEL
PRESSURE RELIEF PROCEDURE” in Section 6-1.
2) Disconnect negative (–) cable from battery.
3) Disconnect vacuum hose (1) from fuel pressure regulator.
4) Remove fuel pressure regulator (1) from fuel delivery pipe
(3).
5) Disconnect fuel return hose (2) from fuel pressure regulator.
CAUTION:
A small amount of fuel may be released when it is from
delivery pipe.
Place a shop cloth under delivery pipe so that released
fuel is absorbed in it.
CAUTION:
A small amount of fuel may be released when hose is dis-
connected. Cover hose to be disconnected with a shop
cloth.
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6E2-26 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
INSTALLATION
For installation, reverse removal procedure and note the follow-
ings.
•Use new O-ring.
•Apply thin coat of gasoline to O-ring to facilitate installation.
•Tighten fuel pressure regulator (1) bolts to specified torque.
Tightening torque
Fuel pressure regulator bolt
(a) : 10 N·m (1.0 kg-m, 7.5 lb-ft)
•With engine “OFF” and ignition switch “ON”, check for fuel
leaks around fuel line connection.
Fuel injector
ON-VEHICLE INSPECTION
1) Using sound scope (1) or such, check operating sound of
injector when engine is running or cranking.
Cycle of operating sound should vary according to engine
speed.
If no sound or an unusual sound is heard, check injector cir-
cuit (wire or coupler) or injector.
2) Disconnect connector from injector, connect ohmmeter
between terminals of injector and check resistance.
If resistance is out of specification, replace.
Fuel injector resistance:
14.2 – 14.8 Ω
Ω Ω Ω (at 20°C, 68°F)
3) Connect connector to injector securely.
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6E2-28 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
1) Install injector (1) and fuel pressure regulator (2) to special
tool (injector checking tool).
Special tool
(A) : 09912-58421
2) Connect special tools (hoses and attachment) to pipes of
vehicle.
Special tool
(B) : 09912-58431
3) Connect special tool (test lead) to injector.
Special tool
(C) : 09930-88521
4) Install suitable vinyl tube onto injector (3) nozzle to prevent
fuel from splashing out when injecting.
5) Put graduated cylinder under injector as far apart as possi-
ble.
6) Disconnect fuel pump relay.
7) To operate fuel pump and apply fuel pressure to injector,
using wire harness (2) as thick as the one used for fuel pump
circuit, connect two terminals of relay connector (1) as
shown in the figure.
8) Apply battery (4) voltage to injector for 15 seconds and mea-
sure injected fuel volume with graduated cylinder.Test each
injector two or three times.If not within specification, replace
injector.
Injected fuel volume:
56 – 60 cc/15 sec. (1.89/1.97 – 2.02/2.11 US/lmp. oz/15 sec.)
9) Check fuel leakage from injector (1) nozzle. Do not operate
injector for this check (but fuel pump should be at work). If
fuel leaks more than following specifications, replace.
Fuel leakage:
Less than 1 drop/min. NOTE:
Remove grommet from injector, then install injector to
special tool and tighten bolts by hand.
[A]: Left-hand steering vehicle
[B]: Right-hand steering vehicle