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Fuel pressure relief procedure
After making sure that engine is cold, release fuel pressure as fol-
lows.
1) Place transmission gear shift lever in “Neutral” (Shift selector
lever 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 its connector.
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
its connector.
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 pres-
sure 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. CAUTION:
This work must not be done when engine is hot. If done
so, it may cause adverse effect to catalyst.
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[A] Fig. 1 for Step 5 / [B] Fig. 2 for Step 7 / [C] Fig. 3 for Step 810 Check 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. 5.
Is fuel return pressure (returning sounds) felt
from fuel feed hose (1) when ignition switch is
turned ON?Go to Step 12. Go to Step 11.
11 Check 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”.
12 Check 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 13. Go to “Ignition Spark Test”
in Section 6F.
13 Check fuel injector for operation as follows :
1) Install spark plugs and connect injector con-
nectors.
2) Using sound scope (2), check operating
sound of each injector (3) when cranking
engine. See Fig. 6.
Was injector operating sound heard from all
injectors?Go to “Engine Diagnosis
Table”.Go to “Diag. Flow Table
B-1”. Step Action Yes No
[B] : When not using SUZUKI scan tool :
[C] : When using SUZUKI scan tool
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Excessive engine oil
consumptionSticky piston ring Pistons, piston rings, connecting rods
and cylinders in Section 6A1.
Worn piston and cylinder Pistons, piston rings, connecting rods
and cylinders in Section 6A1.
Worn piston ring groove and ring Pistons, piston rings, connecting rods
and cylinders in Section 6A1.
Improper location of piston ring gap Pistons, piston rings, connecting rods
and cylinders in Section 6A1.
Worn or damaged valve stem seal Valves and cylinder head in Section
6A1.
Worn valve stem Valves and cylinder head in Section
6A1.
Low oil pressure
Improper oil viscosity ITEM1-3 Engine oil and oil filter
change in Section 0B.
Malfunctioning oil pressure switch Oil pressure switch in Section 8.
Clogged oil strainer Oil pan and oil pump strainer in Sec-
tion 6A1.
Functional deterioration of oil pump Oil pump in Section 6A1.
Worn oil pump relief valve Oil pump in Section 6A1.
Excessive clearance in various sliding
partsRefer to Section 6A1.
Engine noise
See NOTE below.Improper valve lash Valve lash in Section 6A1.
Worn valve stem and guide Valves and cylinder head in Section
6A1.
Weak or broken valve spring Valve springs in Section 6A1.
Warped or bent valve Valves and cylinder head in Section
6A1.
Loose camshaft housing bolts Camshaft in Section 6A1.
Worn piston, ring and cylinder bore Pistons and cylinders in Section 6A1.
Worn crankpin bearing Crankpin and connecting rod bearing
in Section 6A1.
Worn crankpin Crankpin and connecting rod bearing
in Section 6A1.
Loose connecting rod nuts Connecting rod in Section 6A1.
Low oil pressure Previously outlined.
Worn crankshaft journal bearing Main bearings, Crankshaft and cylin-
der block in Section 6A1.
Worn crankshaft journal Main bearings, Crankshaft and cylin-
der block in Section 6A1.
Loose lower crankcase (bearing cap) bolts Main bearings, Crankshaft and cylin-
der block in Section 6A1.
Excessive crankshaft thrust play Main bearings, Crankshaft and cylin-
der block in Section 6A1. Condition Possible Cause Reference Item
NOTE:
Before checking the mechanical noise, make sure that :
Ignition timing is properly adjusted.
Specified spark plug is used.
Specified fuel is used.
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Scan Tool Data
As the data values given below are standard values estimated on the basis of values obtained from the normally
operating vehicles by using a scan tool, use them as reference values. Even when the vehicle is in good condi-
tion, there may be cases where the checked value does not fall within each specified data range. Therefore,
judgment as abnormal should not be made by checking with these data alone.
Also, conditions in the below table that can be checked by the scan tool are those detected by ECM and output
from ECM as commands and there may be cases where the engine or actuator is not operating (in the condi-
tion) as indicated by the scan tool. Be sure to use the timing light to check the ignition timing.
NOTE:
With the generic scan tool, only star (
✱
✱✱ ✱) marked data in the table below can be read.
The triangle (
∆
∆∆ ∆) marked data in the table below can not be read for vehicle without immobilizer indi-
cator lamp at combination meter.
When checking the data with the engine running at idle or racing, be sure to shift M/T gear to the
neutral gear position and A/T gear to the “Park” position and pull the parking brake fully. Also, if
nothing or “no load” is indicated, turn OFF A/C, all electric loads, P/S and all the other necessary
switches.
SCAN TOOL DATA CONDITION REFERENCE VALUES
✱
✱✱ ✱FUEL SYSTEM B1 (FUEL
SYSTEM STATUS)At specified idle speed after warming up CLOSED (closed loop)
✱
✱✱ ✱
CALC LOAD
(CALCULATED LOAD
VALUE)At specified idle speed with no load after
warming up3 – 9 %
At 2500 r/min with no load after warming up 12 – 17 %
✱
✱✱ ✱COOLANT TEMP.
(ENGINE COOLANT
TEMP.)At specified idle speed after warming up 80 – 100 °C, 176 – 212 °F
✱
✱✱ ✱SHORT FT B1 (SHORT
TERM FUEL TRIM)At specified idle speed after warming up– 20 – +20 %
✱
✱✱ ✱LONG FT B1 (LONG TERM
FUEL TRIM)At specified idle speed after warming up– 15 – +15 %
✱
✱✱ ✱MAP (INTAKE MANIFOLD
ABSOLUTE PRESSURE)At specified idle speed with no load after30 – 37 kPa,
220 – 340 mmHg
✱
✱✱ ✱
ENGINE SPEED At idling with no load after warming upDesired idle speed
±50 r/min
✱
✱✱ ✱VEHICLE SPEED At stop 0 km/h, 0 MPH
✱
✱✱ ✱IGNITION ADVANCE
(IGNITION TIMING
ADVANCE FOR NO.1 CYL-
INDER)At specified idle speed with no load after
warming up5 – 16° BTDC
✱
✱✱ ✱
INTAKE AIR TEMP. At specified idle speed after warming upAmbient temp. :
+15 °C (59 °F)
–5 °C (23 °F)
✱
✱✱ ✱MAF (MASS AIR FLOW
RATE)At specified idle speed with no load after
warming up1 – 4 gm/sec
✱
✱✱ ✱
THROTTLE POS
(THROTTLE POSITION)Ignition switch
ON / engine
stoppedThrottle valve fully closed 7 – 18 %
Throttle valve fully open 70 – 90 %
✱
✱✱ ✱O2S B1 S1 (HEATED OXY-
GEN SENSOR-1)At specified idle speed after warming up 0.01 – 0.95 V
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Scan tool data definitions
FUEL SYSTEM (FUEL SYSTEM STATUS)
Air / fuel ratio feedback loop status displayed as either open or closed loop. Open indicates that ECM ignores
feedback from the exhaust oxygen sensor.
Closed indicates final injection duration is corrected for oxygen sensor feedback.
CALC LOAD (CALCULATED LOAD VALUE, %)
Engine load displayed as a percentage of maximum possible load. Value is calculated mathematically using the
formula : actual (current) intake air volume ÷ maximum possible intake air volume x 100%.
COOLANT TEMP. (ENGINE COOLANT TEMPERATURE, °C, °F)
It is detected by engine coolant temp. sensor
SHORT FT B1 (SHORT TERM FUEL TRIM, %)
Short term fuel trim value represents short term corrections to the air / fuel mixture computation. A value of 0
indicates no correction, a value greater than 0 means an enrichment correction, and a value less than 0 implies
an enleanment correction.
LONG FT B1 (LONG TERM FUEL TRIM, %)
Long term fuel trim Value represents long term corrections to the air / fuel mixture computation. A value of 0 indi-
cates no correction, a value greater than 0 means an enrichment correction, and a value less than 0 implies an
enleanment correction.
MAP (INTAKE MANIFOLD ABSOLUTE PRESSURE, kPa, inHg)
It is detected by manifold absolute pressure sensor and used (among other things) to compute engine load.
ENGINE SPEED (rpm)
It is computed by reference pulses from crankshaft position sensor.
VEHICLE SPEED (km/h, MPH)
It is computed based on pulse signals from vehicle speed sensor.
IGNITION ADVANCE (IGNITION TIMING ADVANCE FOR NO.1 CYLINDER, °)
Ignition timing of NO.1 cylinder is commanded by ECM. The actual ignition timing should be checked by using
the timing light.
INTAKE AIR TEMP. (°C, °F)
It is detected by intake air temp. sensor and used to determine the amount of air passing into the intake manifold
as air density varies with temperature.
MAF (MASS AIR FLOW RATE, gm/s, lb/min)
It represents total mass of air entering intake manifold which is computed based on signals from MAP sensor,
IAT sensor, TP sensor, etc.BRAKE SWIgnition switch
ONBrake pedal is depressing ON
Brake pedal is releasing OFF
BLOWER FANIgnition switch
ONBlower fan switch ON ON
Blower fan switch OFF OFF
A/C MAG CLUTCHIgnition switch
ONA/C operating ON
A/C not operating OFF SCAN TOOL DATA CONDITION REFERENCE VALUES
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FUEL TANK LEVEL (%)
This parameter indicates approximate fuel level in the fuel tank. As the detectable range of the fuel level sensor
is set as 0 to 100%, however, with some models whose fuel tank capacity is smaller, the indicated fuel level may
be only 70% even when the fuel tank is full.
PNP SIGNAL (PARK / NEUTRAL POSITION SIGNAL, P/N RANGE or D RANGE)
It is detected by signal from TCM.
D range : A/T is in “R”, “D”, “2” or “L” range.
P/N range : A/T is in “P” or “N” range or the above signal is not inputted from TCM.
EGR VALVE (%)
This parameter indicates opening rate of EGR valve which controls the amount of EGR flow.
PSP SW
The Power Steering Pressure switch parameter displays ON when steering wheel is turned all the way to the
right or left.
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ECM TERMINAL VOLTAGE VALUES TABLE
For TYPE A (See NOTE)
NOTE:
Type A is other than follows.
Type B is left hand steering vehicle equipped with fasten seat belt light and EGR valve or right hand
steering vehicle equipped with fasten seat belt light and immobilizer control system.
TERMINAL
NO.CIRCUIT NORMAL
VOLTAGECONDITION
E191Ground––
2Ground––
3Ground––
4 EVAP canister purge valve 10 – 14 V Ignition switch ON
5Power steering pressure switch
(if equipped)0 – 1.3 VWhile engine running at idle speed, turn
steering wheel to right or left as far as it
stops
10 – 14 V Ignition switch ON
6 Idle air control valve 0 – 13 VAt specified idle speed after engine
warmed up
7 Heater of HO2S-1 10 – 14 V Ignition switch ON
8 Fuel injector NO.4 10 – 14 V Ignition switch ON
9 Fuel injector NO.1 10 – 14 V Ignition switch ON
10 Sensor ground––
11 Camshaft position sensor0 – 0.8 V and
4 – 6 VIgnition switch ON
12–– –
13Heater oxygen sensor-1 Refer to DTC P0130 diag. flow table
CO adjusting resistor (w/o HO2S) 0 – 5 V Ignition switch ON position
14
Engine coolant temp. sensor 0.55 - 0.95 VIgnition switch ON
Engine coolant temp. : 80 °C (176 °F)
15
Intake air temp. sensor 2.0 – 2.7 VIgnition switch ON
Intake air temp. : 20 °C (68 °F)
16 Throttle opening signal0.2 – 1.0 VIgnition switch ON position and throttle
valve at idle position
2.8 – 4.8 VIgnition switch ON position and throttle
valve fully open
17EGR valve (stepper motor coil 3, if
equipped)10 – 14 VIgnition switch ON position leaving engine
OFF
18EGR valve (stepper motor coil 1, if
equipped)10 – 14 VIgnition switch ON position leaving engine
OFF
19 Ignition coil #2––
20 Ignition coil #1––
21 Fuel injector NO.2 10 – 14 V Ignition switch ON
22 Power source for sensors 4.75 – 5.25 V Ignition switch ON
23 Crankshaft position sensor0 – 0.8 or
4 – 5 VIgnition switch ON position
24–– –
25 Knock sensor About 2.5 VAt specified idle speed after engine
warmed up
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For TYPE B (See NOTE)
E1926 Manifold absolute pressure sensor 3.3 – 4.0 VIgnition switch ON
Barometric pressure : 100 kPa
(760 mmHg)
27 A/C evaporator temp. sensor 2.0 – 2.3 VIgnition switch ON A/C evaporation temp.
sensor at 25 °C (77 °F)
28EGR valve (stepper motor coil 4, if
equipped)10 – 14 VIgnition switch ON position leaving engine
OFF
29EGR valve (stepper motor coil 2, if
equipped)10 – 14 VIgnition switch ON position leaving engine
OFF
30–– –
31 Fuel injector NO.3 10 – 14 V Ignition switch ON TERMINAL
NO.CIRCUIT NORMAL
VOLTAGECONDITION
NOTE:
See NOTE in “ECM TERMINAL VOLTAGE VALUES TABLE” for applicable model.
TERMINAL
NO.CIRCUIT NORMAL
VOLTAGECONDITION
E191 Ground––
2 Ground––
3 Ground––
4 EVAP canister purge valve 10 – 14 V Ignition switch ON
5Power steering pressure switch
(if equipped)0 – 1.3 VWhile engine running at idle speed, turn
steering wheel to right or left as far as it
stops
10 – 14 V Ignition switch ON
6 Idle air control valve 0 – 13 VAt specified idle speed after engine
warmed up
7 Heater of HO2S-1 10 – 14 V Ignition switch ON
8 Fuel injector NO.4 10 – 14 V Ignition switch ON
9 Fuel injector NO.1 10 – 14 V Ignition switch ON
10 Sensor ground––
11 Camshaft position sensor0 – 0.8 V and
4 – 6 VIgnition switch ON
12–– –
13Heater oxygen sensor-1 Refer to DTC P0130 diag. flow table
CO adjusting resistor (w/o HO2S) 0 – 5 V Ignition switch ON position
14 Engine coolant temp. sensor 0.55 - 0.95 VIgnition switch ON
Engine coolant temp. : 80 °C (176 °F)
15 Intake air temp. sensor 2.0 – 2.7 VIgnition switch ON
Intake air temp. : 20 °C (68 °F)
16 Throttle opening signal0.2 – 1.0 VIgnition switch ON position and throttle
valve at idle position
2.8 – 4.8 VIgnition switch ON position and throttle
valve fully open
17EGR valve (stepper motor coil 3, if
equipped)10 – 14 VIgnition switch ON position leaving engine
OFF