Engine and emission control system SUZUKI GRAND VITARA 1999 2.G Owner's Manual

6E2-14 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
Accelerator Cable Adjustment
1) With throttle valve closed, check accelerator pedal play
which should be within following specification.
If measured value is out of specification, adjust accelerator
cable (1) to specification with cable adjusting nut (2).
Accelerator pedal play “a”:
2 – 5 mm (0.08 – 0.20 in.)
2) With accelerator pedal depressed fully, check clearance
between throttle lever (2) and lever stopper (1) (throttle body)
which should be within following specification.
If measured value is out of specification, adjust it to specifi-
cation by changing height of pedal stopper bolt (3).
Clearance “b” between throttle lever and lever stopper
(throttle body) (with accelerator pedal depressed fully):
0.5 – 2.0 mm (0.02 – 0.07 in.)
A/T Throttle Cable Adjustment (A/T Vehicle)
1) Make sure that accelerator cable is adjusted as specified.
2) With throttle valve closed, check clearance “c” which should
be within the following specification.
If it is out of specification, adjust A/T throttle cable (1) by
turning cable adjusting nut (2).
A/T throttle cable installing position specification clear-
ance “c”:
0.8 – 1.5 mm (0.03 – 0.06 in.)

ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-15
Idle Speed/Idle Air Control (IAC) Duty Inspec-
tion
Before idle speed/IAC duty check, make sure of the following.
•Lead wires and hoses of engine/emission control systems
are connected securely.
•Accelerator cable is adjusted.
•Ignition timing is within specification.
•All accessories (wipers, heater, lights, A/C, etc.) are out of
service.
•Air cleaner has been properly installed and is in good condi-
tion.
•ECM (PCM) does not detect any malfunction DTC.
After above items are all confirmed, check idle speed and IAC
duty as follows.
[Using SUZUKI scan tool]
1) Connect SUZUKI scan tool to DLC with ignition switch OFF.
Special tool
(A) : SUZUKI scan tool
2) Warm up engine to normal operating temperature.
3) Check IAC duty and idle speed by using “Data List” mode of
SUZUKI scan tool.
Engine idle speed:
A/C OFF: 700 ± 50 r/min.
A/C ON: 750 ± 50 r/min.
IAC duty at specified idle speed:
5 – 40 % (at A/C OFF)
4) If duty and/or idle speed is out of specifications, check idle
air control system referring to “DIAG. FLOW TABLE B-4” in
Section 6-1.
5) Check that specified engine idle speed is obtained with A/C
ON if vehicle is equipped with A/C. If not, check A/C ON sig-
nal circuit and idle air control system. NOTE:
Before starting engine, place transmission gear shift
lever in “Neutral” (shift selector lever to “P” range for A/T
vehicle), and set parking brake and block drive wheels.

6E2-16 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
[Not using SUZUKI scan tool] (vehicle with monitor
connector)
1) Disconnect scan tool from DLC if connected.
2) Warm up engine to normal operating temperature.
3) Stop engine and connect duty meter (3) between duty output
terminal and ground terminal of monitor connector (1).
4) Using service wire (2), ground diagnosis switch terminal in
monitor connector.
5) Set tachometer.
6) Start engine and warm it up completely.
7) Check IAC duty and idle air control system referring to Diag-
nostic Flow Table B-4 “IDLE AIR CONTROL SYSTEM
CHECK” in this section.
•“OFF DUTY METER” is such duty meter that indicates
approx. 100% when terminal voltage is approx. “0 V”.
•“V
B” represents battery voltage while engine of vehicle being
checked is running.
8) Remove service wire from monitor connector.
9) Install cap to monitor connector.
10) Check that specified engine idle speed is obtained with A/C
ON if vehicle is equipped with A/C.
If not, check A/C ON signal circuit and idle air control sys-
tem.
A: Output duty select switch terminal
B: Diagnosis switch terminal
C: Blank
D: Ground terminal
E: Test switch terminal
F: Duty output terminal
A/C OFF A/C ON
Engine idle speed: 700 ± 50 r/min. 750 ± 50 r/min.
IAC duty at specified
idle speed:5 – 40 % (0.7 – 5.6 V
when battery voltage
is 14 V)–
NOTE:
IAC duty can be checked roughly by using voltmeter. I
AC duty to voltage relation is as follows.
ON DUTY METER
INDICATION
(%)OFF DUTY
INDICATION
(%)VOLT METER
INDICATION
(V)
0
50
10010
50
00
0.5 x V
B
VB

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.

6E2-18 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
Air Intake System
Throttle body
REMOVAL
1) Disconnect negative (–) cable at battery.
2) Drain cooling system.
3) Remove strut tower bar.
4) Disconnect accelerator cable (1) and or A/T throttle cable (2)
from throttle body.
5) Disconnect water hoses from throttle body.
1. Throttle body 4. Water hose
2. Intake collector 5. MAF sensor
3. Breather hose 6. TP sensor

ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE) 6E2-19
6) Remove surge tank cover.
Remove intake air pipe (1) and surge tank pipe (2).
7) Disconnect connectors of TP sensor and IAC valve.
8) Disconnect ground wire at connector.
9) Remove clamp bracket (1) and harness clamps from intake
collector.
10) Disconnect connectors of EVAP canister purge valve (1),
MAP sensor and EGR valve (5).
11) Disconnect PCV valve (6) from cylinder head with hose con-
nected, breather hose (3) from cylinder head and EVAP can-
ister purge valve hose (2).
12) Detach EGR pipe (4) from intake air collector.
13) Remove throttle body (3) and intake collector (2) from intake
manifold (1).
14) Disconnect hoses of PCV from throttle body.
15) Remove throttle body from intake collector.
NOTE:
TP sensor (4), or other components containing rubber
must not be placed in a solvent or cleaner bath. A
chemical reaction will cause these parts to swell,
harden or get distorted.
Don’t put drills or wires into passages for cleaning. It
causes damages in passages.

6E2-20 ENGINE AND EMISSION CONTROL SYSTEM (SEQUENTIAL MULTIPORT FUEL INJECTION FOR H27 ENGINE)
CLEANING
Clean throttle body bore and bypass air passages (1) by blowing
compressed air.
INSTALLATION
1) Clean mating surfaces and install throttle body gasket to
intake collector (1) with new gasket (2).
2) Install throttle body to intake collector and tighten bolts.
3) Connect PCV hose.
4) Install throttle body and intake collector to intake manifold
with new intake collector gaskets.
5) Install EGR pipe with new gaskets.
6) Connect breather hose and EVAP canister purge valve hose
and install PCV valve to cylinder head.
7) Connect connectors of EVAP canister purge valve, MAP
sensor and EGR valve.
Fix wire harness with clamps.
8) Install clamp bracket to intake collector.
9) Connect ground wire connector.
10) Connect connectors of TP sensor, ground and IAC valve.
11) Install surge tank pipe to intake manifold with new gaskets
and intake air pipe to throttle body. Install surge tank cover.
12) Connect engine coolant hoses to throttle body.
13) Connect accelerator cable and A/T throttle cable (A/T).CAUTION:
Do not blow compressed air through bypass air pas-
sage with IAC valve installed to throttle body. This will
cause IAC valve to malfunction.
TP sensor, idle air control valve or other components
containing rubber must not be places in a solvent or
cleaner bath.
A chemical reaction will cause these parts to swell,
harden or get distorted.

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”

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.

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