ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-5
FUEL PRESSURE RELIEF PROCEDURE
CAUTION:
This work must not be done when engine is hot. If done so,
it may cause adverse effect to catalyst.
After making sure that engine is cold, release fuel pressure as fol-
lows.
1) Place transmission gear shift lever in “Neutral” (Shift selector le-
ver to “P” range for A / T model), set parking brake, and block
drive wheels.
2) Remove relay box cover.
3) Disconnect fuel pump relay (1) from relay box.
4) Remove fuel filler cap to release fuel vapor pressure in fuel tank
and then reinstall it.
5) Start engine and run it till it stops for lack of fuel. Repeat cranking
engine 2-3 times for about 3 seconds each time to dissipate fuel
pressure in lines. Fuel connections are now safe for servicing.
6) Upon completion of servicing, connect fuel pump relay (1) to
relay box and install relay box cover.
FUEL LEAKAGE CHECK PROCEDURE
After performing any service on fuel system, check to make sure
that there are no fuel leakages as follows.
1) Turn ON ignition switch for 3 seconds (to operate fuel pump) and
then turn it OFF.
Repeat this (ON and OFF) 3 or 4 times and apply fuel pressure
to fuel line. (till fuel pressure is felt by hand placed on fuel feed
hose.)
2) In this state, check to see that there are no fuel leakages from
any part of fuel system.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-9
PRECAUTION IN DIAGNOSING TROUBLE
Don’t disconnect couplers from ECM (PCM), battery cable from
battery, ECM (PCM) ground wire harness from engine or main
fuse before confirming diagnostic information (DTC, freeze frame
data, etc.) stored in ECM (PCM) memory. Such disconnection will
erase memorized information in ECM (PCM) memory.
Diagnostic information stored in ECM (PCM) memory can be
cleared as well as checked by using SUZUKI scan tool (Tech-1)
or generic scan tool. Before using scan tool, read its Operator’s
(Instruction) Manual carefully to have good understanding as to
what functions are available and how to use it.
Priorities for diagnosing troubles
If two or more DTCs are stored, proceed to the flow table of the
DTC which was detected earliest in the order and follow the
instruction in that table.
If no instructions are given, troubleshoot DTCs according to the
following priorities.
1. Diagnostic trouble codes (DTCs) other than DTC
P0171 / P0172 (Fuel system too lean / too rich), DTC
P0300 / P0301 / P0302 / P0303 / P0304 (Misfire detected) and
DTC P0400 (EGR flow malfunction)
2. DTC P0171 / P0172 (Fuel system too lean / too rich) and DTC
P0400 (EGR flow malfunction)
3. DTC P0300 / P0301 / P0302 / P0303 / P0304 (Misfire detected)
Be sure to read “Precautions for Electrical Circuit Service” in Sec-
tion 0A before inspection and observe what is written there.
ECM (PCM) Replacement
When substituting a known-good ECM (PCM), check for following
conditions. Neglecting this check may cause damage to a known-
good ECM (PCM).
–Resistance value of all relays, actuators is as specified respec-
tively.
–MAP sensor and TP sensor are in good condition and none of
power circuits of these sensors is shorted to ground.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-13
MALFUNCTION INDICATOR LAMP (MIL)
CHECK
1) Turn ON ignition switch (but the engine at stop) and check that
MIL lights.
If MIL does not light up (or MIL dims), go to “Diagnostic Flow
Table A-1” for troubleshooting.
2) Start engine and check that MIL turns OFF.
If MIL remains ON and no DTC is stored in ECM (PCM), go to
“Diagnostic Flow Table A-2” for troubleshooting.
DIAGNOSTIC TROUBLE CODE (DTC) CHECK
1) Prepare SUZUKI scan tool (Tech-1).
2) With ignition switch OFF, connect it to data link connector (DLC)
(1) located on underside of instrument panel at driver’s seat side.
Special Tool:
(A): SUZUKI scan tool
(B): Mass storage cartridge
(C): 16 / 14 pin DLC cable
3) Turn ignition switch ON and confirm that MIL lights.
4) Read DTC, pending DTC and freeze frame data according to
instructions displayed on scan tool and print it or write it down.
Refer to scan tool operator’s manual for further details.
If communication between scan tool and ECM (PCM) is not pos-
sible, check if scan tool is communicable by connecting it to
ECM (PCM) in another vehicle. If communication is possible in
this case, scan tool is in good condition. Then check data link
connector and serial data line (circuit) in the vehicle with which
communication was not possible.
5) After completing the check, turn ignition switch off and discon-
nect scan tool from data link connector.
6-1-14 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
DIAGNOSTIC TROUBLE CODE (DTC)
CLEARANCE
[Using SUZUKI scan tool]
1) Connect SUZUKI scan tool (Tech-1) to data link connector in the
same manner as when making this connection for DTC check.
2) Turn ignition switch ON.
3) Erase DTC and pending DTC according to instructions dis-
played on scan tool. Refer to scan tool operator’s manual for fur-
ther details.
4) After completing the clearance, turn ignition switch off and dis-
connect scan tool from data link connector.
NOTE:
DTC and freeze frame data stored in ECM (PCM) memory
are also cleared in following cases. Be careful not to clear
them before keeping their record.
When power to ECM (PCM) is cut off (by disconnecting
battery cable, removing fuse or disconnecting ECM
(PCM) connectors)
When the same malfunction (DTC) is not detected again
during 40 engine warm-up cycles.
[Not using SUZUKI scan tool]
1) Turn the ignition switch OFF position.
2) Disconnect battery negative cable for specified time below to
erase diagnostic trouble code stored in ECM (PCM) memory
and reconnect it.
Time required to erase DTC:
Ambient
temperatureTime to cut power
to ECM (PCM)
Over 0C (32F)30 sec. or longer
Under 0C (32F)
Not specifiable.
Select a place with higher
than 0C (32F) temperature.
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-19
Operation
VISUAL INSPECTION
Visually check following parts and systems.
INSPECTION ITEM
REFERRING SECTION
Engine oil ––––– level, leakage
Engine coolant ––––– level, leakage
Fuel ––––– level, leakage
A / T fluid ––––– level, leakage
Air cleaner element ––––– dirt, clogging
Battery ––––– fluid level, corrosion of terminal
Water pump belt ––––– tension, damage
Throttle cable ––––– play, installation
Vacuum hoses of air intake system ––––– disconnection,
looseness, deterioration, bend
Connectors of electric wire harness ––––– disconnection, friction
Fuses ––––– burning
Parts ––––– installation, bolt ––––– looseness
Parts ––––– deformation
Other parts that can be checked visually
Also check following items at engine start, if possible
Malfunction indicator lamp
Charge warning lamp
Engine oil pressure warning lamp
Engine coolant temp. meter
Fuel level meter
Tachometer, if equipped
Abnormal air being inhaled from air intake system
Exhaust system ––––– leakage of exhaust gas, noise
Other parts that can be checked visuallySection 0B
Section 0B
Section 0B
Section 0B
Section 0B
Section 0B
Section 6E2
Section 8
Section 6
Section 6H
Section 8 (Section 6 for pressure check)
Section 8
Section 8
6-1-20 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
ENGINE BASIC INSPECTION
This check is very important for troubleshooting when ECM (PCM) has detected no DTC and no abnormality has
been found in visual inspection.
Follow the flow table carefully.
STEP
ACTIONYESNO
1Was “ENGINE DIAG. FLOW TABLE” performed?Go to Step 2.Go to “ENGINE DIAG.
FLOW TABLE”.
2Check battery voltage.
Is it 11 V or more?Go to Step 3.Charge or replace
battery.
3Is engine cranked?Go to Step 4.Go to “DIAGNOSIS”
in Section 6G.
4Does engine start?Go to Step 5.Go to Step 7.
5Check idle speed as follows:
1) Warm up engine to normal operating temp.
2) Shift transmission to neutral position for M / T
(“P” position for A / T).
3) All of electrical loads are switched off.
4) Check engine idle speed with scan tool.
See Fig. 1.
Is it 700 – 800 r / min?Go to Step 6.“ENGINE DIAGNO-
SIS TABLE” in this
section.
6Check ignition timing as follows:
1) Using SUZUKI scan tool, select “MISC” mode on
SUZUKI scan tool and fix ignition timing to initial
one. See Fig. 2.
2) Remove air cleaner bolt and shift air cleaner
position to observe ignition timing.
3) Using timing light (1), check initial ignition timing.
See Fig. 3.
Is it 5 ± 3 BTDC at specified idle speed?“ENGINE DIAGNO-
SIS TABLE” in this
section.Check ignition control
related parts referring
to Section 6F1.
7Check fuel supply as follows:
1) Check to make sure that enough fuel is filled in fuel
tank.
2) Turn ON ignition switch for 2 seconds and then
OFF. See Fig. 4.
Is fuel return pressure (returning sounds) felt from fuel
feed hose (1) when ignition switch is turned ON?Go to Step 9.Go to Step 8.
8Check fuel pump for operating.
1) Was fuel pump operating sound heard from fuel
filler for about 2 seconds after ignition switch ON
and stop?Go to “DIAG. FLOW
TABLE B-3”.Go to “DIAG. FLOW
TABLE B-2”.
9Check ignition spark as follows:
1) Disconnect injector couplers.
2) Remove spark plugs and connect them to high
tension cords.
3) Ground spark plugs.
4) Crank engine and check if each spark plug sparks.
Is it in good condition?Go to Step 10.Go to “DIAGNOSIS”
in Section 6F1.
10Check fuel injector for operation as follows:
1) Install spark plugs and connect injector
connectors.
2) Using sound scope (1), check operating sound of
each injector (2) when cranking engine. See Fig. 5.
Was injector operating sound heard from all
injectors?“ENGINE DIAGNO-
SIS TABLE” in this
section.Go to “DIAG. FLOW
TABLE B-1”.
Select “DATA
LIST” modeSELECT MENU
F4: MISC TEST When using SUZUKI scan tool
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-21
Fig. 1 for Step 5 Fig. 2 for Step 6 Fig. 3 for Step 6
Fig. 4 for Step 7 Fig. 5 for Step 10
6-1-22 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
ENGINE DIAGNOSIS TABLE
Perform troubleshooting referring to following table when ECM (PCM) has detected no DTC and no abnormality
has been found in visual inspection and engine basic inspection previously.
Condition
Possible CauseReferring Item
Hard Starting
(Engine cranks OK)Ignition system out of order
Faulty spark plug
Leaky high-tension cord
Loose connection or disconnection of high-
tension cords or lead wires
Faulty ignition coil
Fuel system out of order
Dirty or clogged fuel hose or pipe
Malfunctioning fuel pump
Air inhaling from intake manifold gasket or
throttle body gasket
Engine and emission control system out of
order
Faulty idle air control system
Faulty ECT sensor or MAP sensor
Faulty ECM (PCM)
Low compression
Poor spark plug tightening or faulty gasket
Compression leak from valve seat
Sticky valve stem
Weak or damaged valve springs
Compression leak at cylinder head gasket
Sticking or damaged piston ring
Worn piston, ring or cylinder
Others
Malfunctioning PCV valve
Spark plugs in Section 6F1
High-tension cords in Section 6F1
High-tension cords in Section 6F1
Ignition coil in Section 6F1
Diagnostic Flow Table B-3
Diagnostic Flow Table B-3
Diagnostic Flow Table B-4
ECT sensor or MAP sensor in
Section 6E2
Compression check in Section
6A1
Spark plugs in Section 6F1
Valves inspection in Section 6A1
Valves inspection in Section 6A1
Valve springs inspection in
Section 6A1
Cylinder head inspection in
Section 6A1
Cylinders, pistons and piston rings
inspection in Section 6A1
Cylinders, pistons and piston rings
inspection in Section 6A1
PCV system in Section 6E2