Downloaded from www.Manualslib.com manuals search engine 6-6 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Engine Diagnosis
General Description
This vehicle is equipped with an engine and emission control system which are under control of ECM.
The engine and emission control system in this vehicle are controlled by ECM. ECM has an On-Board Diagnos-
tic system which detects a malfunction in this system and abnormality of those parts that influence the engine
exhaust emission. When diagnosing engine troubles, be sure to have full understanding of the outline of “On-
Board Diagnostic System” and each item in “Precaution in Diagnosing Trouble” and execute diagnosis accord-
ing to “ENGINE DIAGNOSTIC FLOW TABLE”.
There is a close relationship between the engine mechanical, engine cooling system, ignition system, exhaust
system, etc. and the engine and emission control system in their structure and operation. In case of an engine
trouble, even when the malfunction indicator lamp (MIL) doesn’t turn ON, it should be diagnosed according to
this flow table.
On-Board Diagnostic System (Vehicle with
Immobilizer Indicator Lamp)
ECM in this vehicle has following functions.
When the ignition switch is turned ON with the engine at a
stop, malfunction indicator lamp (MIL) (1) turns ON to check
the bulb of the malfunction indicator lamp (1).
When ECM detects a malfunction which gives an adverse
effect to vehicle emission while the engine is running, it
makes the malfunction indicator lamp (1) in the meter cluster
of the instrument panel turn ON or flash (flashing only when
detecting a misfire which can cause damage to the catalyst)
and stores the malfunction area in its memory.
(If it detects that continuously 3 driving cycles are normal
after detecting a malfunction, however, it makes MIL (1) turn
OFF although DTC stored in its memory will remain.)
As a condition for detecting a malfunction in some areas in
the system being monitored by ECM and turning ON the
malfunction indicator lamp (1) due to that malfunction, 2 driv-
ing cycle detection logic is adopted to prevent erroneous
detection.
When a malfunction is detected, engine and driving condi-
tions then are stored in ECM memory as freeze frame data.
(For the details, refer to description on Freeze frame data.)
It is possible to communicate by using not only SUZUKI scan
tool (2) but also generic scan tool. (Diagnostic information
can be accessed by using a scan tool.)
WARM-UP CYCLE
A warm-up cycle means sufficient vehicle operation such that the
coolant temperature has risen by at least 22 °C (40 °F) from
engine starting and reaches a minimum temperature of 70 °C
(160 °F).
Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-9
On-Board Diagnostic System (Vehicle without
Immobilizer Indicator Lamp)
ECM diagnosis troubles which may occur in the area including
the following parts when the ignition switch is ON and the engine
is running, and indicates the result by turning on or flashing mal-
function indicator lamp (1).
Heated oxygen sensor (if equipped)
ECT sensor
TP sensor
IAT sensor
MAP sensor
CMP sensor
CKP sensor
Knock sensor
VSS
CPU (Central Processing Unit) of ECM
ECM and malfunction indicator lamp (1) operate as follows.
Malfunction indicator lamp (1) lights when the ignition switch
is turned ON (but the engine at stop) with the diagnosis
switch terminal ungrounded regardless of the condition of
Engine and Emission Control system. This is only to check
the malfunction indicator lamp (1) bulb and its circuit.
If the above areas of Engine and Emission Control system is
free from any trouble after the engine start (while engine is
running), malfunction indicator lamp (1) turns OFF.
When ECM detects a trouble which has occurred in the
above areas, it makes malfunction indicator lamp (1) turn ON
while the engine is running to warn the driver of such occur-
rence of trouble and at the same time it stores the trouble
area in ECM back-up memory. (The memory is kept as it is
even if the trouble was only temporary and disappeared
immediately. And it is not erased unless the power to ECM is
shut off for specified time below.)
ECM also indicates trouble area in memory by means of
flashing of malfunction indicator lamp (1) at the time of
inspection. (i.e. when connecting diagnosis switch terminal
(2) and ground terminal (4) of monitor connector (3) with a
service wire (5) and ignition switch is turned ON.)
NOTE:
When a trouble occurs in the above areas and disap-
pears soon while the diagnosis switch terminal is
ungrounded and the engine is running, malfunction
indicator lamp (1) lights and remains ON as long as the
trouble exists but it turns OFF when the normal condi-
tion is restored.
Time required to erase diagnostic trouble code mem-
ory thoroughly varies depending on ambient tempera-
ture as follows.
Downloaded from www.Manualslib.com manuals search engine 6-24 ENGINE GENERAL INFORMATION AND DIAGNOSIS
Engine has no power
Engine overheating Refer to “Overheating” of this table.
Faulty ignition coil Ignition coil assembly in Section 6F.
Faulty knock sensor Knock sensor malfunction in this sec-
tion.
Fuel pressure out of specification Diagnostic Flow Table B-3
Faulty injector Diagnostic Flow Table B-1
Faulty TP sensor, ECT sensor or MAP
sensorTP sensor, ECT sensor or MAP sen-
sor in Section 6E.
Faulty ECM Inspection of ECM and its circuit in
this section.
Malfunctioning EGR valve (if equipped) EGR system in Section 6E.
Maladjusted accelerator cable play Accelerator cable adjustment in Sec-
tion 6E.
Low compression Previously outlined.
Dragging brakes Diagnosis table in Section 5.
Slipping clutch Diagnosis table in Section 7C.
Improper engine idling
or engine fails to idleFaulty ignition coil Ignition coil assembly in Section 6F.
Engine overheating Refer to “Overheating” of this table.
Fuel pressure out of specification Diagnostic Flow Table B-3
Faulty idle air control system Diagnostic Flow Table B-4
Faulty evaporative emission control sys-
temEVAP control system in Section 6E.
Faulty injector Diagnostic Flow Table B-1
Faulty ECT sensor, TP sensor or MAP
sensorECT sensor, TP sensor or MAP sen-
sor in Section 6E.
Malfunctioning PCV system PCV system in Section 6F.
Faulty ECM Inspection of ECM and its circuit in
this section.
Faulty EGR system (if equipped) EGR system in Section 6E.
Low compression Previously outlined.
Engine hesitates
(Momentary lack of
response as the accel-
erator is depressed.
Can occur at all vehicle
speeds.
Usually most severe
when first trying to
make the vehicle move,
as from a stop sign.)Faulty ignition coil Ignition coil assembly in Section 6F.
Engine overheating Refer to “Overheating” of this table.
Fuel pressure out of specification Diagnostic Flow Table B-3
Faulty injector Diagnostic Flow Table B-1
Faulty TP sensor, ECT sensor or MAP
sensorTP sensor, ECT sensor or MAP sen-
sor in Section 6E.
Faulty ECM Inspection of ECM and its circuit in
this section.
Malfunctioning EGR valve (if equipped) EGR system in Section 6E.
Low compression Previously outlined.
Surges
(Engine power variation
under steady throttle or
cruise.
Feels like the vehicle
speeds up and down
with no change in the
accelerator pedal.)Faulty ignition coil or high-tension cord Ignition coil assembly or high-tension
cords in Section 6F.
Variable fuel pressure Diagnostic Flow Table B-3
Faulty MAP sensor MAP sensor in Section 6E.
Faulty injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Malfunctioning EGR valve (if equipped) EGR system in Section 6E. Condition Possible Cause Reference Item
Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-27
Condition Possible Cause Reference Item
Excessive hydrocar-
bon (HC) emission or
Excessive carbon mon-
oxide (CO) emissionFaulty ignition coil Ignition coil assembly in Section 6F.
Fuel pressure out of specification Diagnostic Flow Table B-3
Lead contamination of three way catalytic
converterMaintenance in Section 6K.
Malfunctioning PCV system PCV system in Section 6E.
Faulty EVAP control system EVAP control system in Section 6E.
Closed loop system (A/F feed back com-
pensation) fails
–Faulty TP sensor
–Faulty ECT sensor or MAP sensor
–Faulty oxygen sensorCheck oxygen sensor output voltage.
Refer to DTC P0130 (No.14) Table in
this section.
Faulty injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Low compression Previously outlined.
Excessive nitrogen
oxides (NOx) emissionFuel pressure out of specification Diagnostic Flow Table B-3
Lead contamination of three way catalytic
converterMaintenance in Section 6K.
Closed loop system (A/F feed back com-
pensation) fails
–Faulty TP sensor
–Faulty ECT sensor or MAP sensor
–Faulty oxygen sensorCheck oxygen sensor output voltage
Refer to DTC P0130 (No.14) Table in
this section.
Faulty injector Diagnostic Flow Table B-1
Faulty ECM Inspection of ECM and its circuit in
this section.
Faulty EGR system (if equipped) EGR system in Section 6E.
Downloaded from www.Manualslib.com manuals search engine 6-72 ENGINE GENERAL INFORMATION AND DIAGNOSIS
DTC P0300 Random Misfire Detected (Misfire Detected at 2 or More Cylinders)
DTC P0301 Cylinder 1 Misfire Detected
DTC P0302 Cylinder 2 Misfire Detected
DTC P0303 Cylinder 3 Misfire Detected
DTC P0304 Cylinder 4 Misfire Detected
CIRCUIT DESCRIPTION
ECM monitors crankshaft revolution speed and engine speed via the crankshaft position sensor and cylinder No.
via the camshaft position sensor. Then it calculates the change in the crankshaft revolution speed and from how
many times such change occurred in every 200 or 1000 engine revolutions, it detects occurrence of misfire.
When ECM detects a misfire (misfire rate per 200 revolutions) which can cause overheat and damage to the
three way catalytic converter, it makes the malfunction indicator lamp (MIL) flash as long as misfire occurs at
that rate.
After that, however, when the misfire rate drops, MIL remains ON until it has been judged as normal 3 times
under the same driving conditions.
Also, when ECM detects a misfire (misfire rate per 1000 revolutions) which will not cause damage to three way
catalytic converter but can cause exhaust emission to be deteriorated, it makes MIL light according to the 2 driv-
ing cycle detection logic.
1. Ignition coil assembly (for No.1 and No.4 cylinder)
2. Ignition coil assembly (for No.2 and No.3 cylinder)
3. Fuel injector
4. CKP sensor
5. CMP sensor
Downloaded from www.Manualslib.com manuals search engine ENGINE FUEL 6C-1
6F1
7A
7A1
7A
7A
7A1
7B1
7C1
7D
7E
7F
8A
8B
8C
6G
6C
6K
9
10
10A
10B
SECTION 6C
ENGINE FUEL
CONTENTS
General Description ....................................... 6C-2
Fuel System ................................................. 6C-2
Fuel Tank ..................................................... 6C-2
Fuel Pump Assembly ................................... 6C-3
Fuel Filler Cap .............................................. 6C-3
On-Vehicle Service......................................... 6C-4Fuel Lines .................................................... 6C-4
Fuel Filler Cap.............................................. 6C-4
Fuel Tank ..................................................... 6C-4
Fuel Pump Assembly ................................... 6C-7
Tightening Torque Specification ................ 6C-10
Special Tool .................................................. 6C-10
CAUTION:
For vehicles with a catalytic converter, be sure to use unleaded fuel only. Use of leaded and/or low
lead fuel can result in engine damage and reduce the effectiveness of the emission control system.
Downloaded from www.Manualslib.com manuals search engine 6C-2 ENGINE FUEL
General Description
Fuel System
The main components of the fuel system are fuel tank, fuel pump assembly with fuel filter and fuel level gauge
and fuel cut valve, fuel feed line, fuel return line and fuel vapor line.
For the details of fuel flow and fuel vapor flow, refer to “Fuel Delivery System” and “Emission Control System” in
Section 6E.
Fuel Tank
The fuel tank is located under the rear section of the vehicle. The
fuel pump assembly is installed in fuel tank. Whenever servicing
the fuel pump assembly, the fuel tank must be removed from the
vehicle.
1. Fuel tank 4. Fuel filler cap 7. Fuel vapor line 10. Fuel filler hose clamp
2. Fuel pump assembly 5. Fuel feed line 8. Fuel filler neck Tightening torque
3. Breather hose 6. Fuel return line 9. Fuel tank mounting bolt
Downloaded from www.Manualslib.com manuals search engine ENGINE AND EMISSION CONTROL SYSTEM 6E-1
6F1
6F2
6G
7C1
7D
7E
7A
7A1
7B1
7C1
7D
7E
7F
8A
8B
8C
8D
6H
6E
10
10A
10B
SECTION 6E
ENGINE AND EMISSION CONTROL SYSTEM
CONTENTS
General Description ....................................... 6E-3
Air Intake System ......................................... 6E-5
Fuel Delivery System ................................... 6E-6
Fuel pump ................................................ 6E-6
Electronic Control System ............................ 6E-7
Engine & emission control input / output
table.......................................................... 6E-8
On-Vehicle Service....................................... 6E-15
Accelerator cable adjustment ................. 6E-15
Idle speed / idle air control (IAC) duty
inspection ............................................... 6E-15
Idle mixture inspection / adjustment
(vehicle without heated oxygen
sensor) ................................................... 6E-17
Air Intake System ....................................... 6E-18
Throttle body .......................................... 6E-18
Idle air control valve (IAC valve)............. 6E-21
Fuel Delivery System ................................. 6E-22
Fuel pressure inspection ........................ 6E-22
Fuel pump .............................................. 6E-23
Fuel pressure regulator .......................... 6E-24
Fuel injector ............................................ 6E-25
Electronic Control System .......................... 6E-29Engine control module (ECM) ................ 6E-29
Manifold absolute pressure sensor (MAP
sensor) ................................................... 6E-29
Throttle position sensor (TP sensor) ...... 6E-30
Intake air temperature sensor
(IAT sensor) ........................................... 6E-31
Engine coolant temperature sensor
(ECT sensor) .......................................... 6E-32
Heated oxygen sensor
(Sensor-1 and sensor-2) ........................ 6E-33
Camshaft position sensor....................... 6E-34
Crankshaft position sensor..................... 6E-35
Vehicle speed sensor (VSS) .................. 6E-36
Fuel level sensor (GAUGE).................... 6E-36
Knock sensor ......................................... 6E-36
Main relay, fuel pump relay and A/C
condenser fan control relay .................... 6E-36
Fuel cut operation .................................. 6E-37
A/C condenser fan control system ......... 6E-37
A/C condenser fan ................................. 6E-37
Output signals of throttle valve opening
and engine coolant temp.
(Vehicle with A/T only) ........................... 6E-38
Emission Control System ........................... 6E-38 WARNING:
For vehicles equipped with Supplemental Restraint (Air Bag) System:
Service on and around the air bag system components or wiring must be performed only by an
authorized SUZUKI dealer. Refer to “Air Bag System Components and Wiring Location View” under
“General Description” in air bag system section in order to confirm whether you are performing ser-
vice on or near the air bag system components or wiring. Please observe all WARNINGS and “Ser-
vice Precautions” under “On-Vehicle Service” in air bag system section before performing service
on or around the air bag system components or wiring. Failure to follow WARNINGS could result in
unintentional activation of the system or could render the system inoperative. Either of these two
conditions may result in severe injury.
Technical service work must be started at least 90 seconds after the ignition switch is turned to the
“LOCK” position and the negative cable is disconnected from the battery. Otherwise, the system
may be activated by reserve energy in the Sensing and Diagnostic Module (SDM).
NOTE:
Whether following systems (parts) are used in the particular vehicle or not depends on specifications.
Be sure to bear this in mind when performing service work.
EGR valve
Heated oxygen sensor (s) or CO adjusting resistor
Three way catalytic converter (TWC) and warm up three-way catalytic converter (WU-TWC)