6-1-6 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
ENGINE DIAGNOSIS
GENERAL DESCRIPTION
This vehicle is equipped with an engine and emission control system which are under control of ECM (PCM).
The engine and emission control system in this vehicle are controlled by ECM (PCM). ECM (PCM) has an On-
Board Diagnostic 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 ac-
cording to “ENGINE DIAGNOSTIC FLOW TABLE”.
There is a close relationship between the engine mechanical, engine cooling system, ignition system, exhaust sys-
tem, 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
ECM (PCM) 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 (PCM) 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 instru-
ment panel turn ON or flash (flashing only when detecting a mis-
fire which can cause damage to the catalyst) and stores the mal-
function area in its memory.
(If it detects that continuously 3 driving cycles are normal after de-
tecting a malfunction, however, it makes MIL (1) turn OFF al-
though DTC stored in its memory will remain.)
As a condition for detecting a malfunction in some areas in the
system being monitored by ECM (PCM) and turning ON the mal-
function indicator lamp (1) due to that malfunction, 2 driving cycle
detection logic is adopted to prevent erroneous detection.
When a malfunction is detected, engine and driving conditions
then are stored in ECM (PCM) 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
(Tech-1) (2) but also generic scan tool. (Diagnostic information
can be accessed by using a scan tool.)
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-15
DIAGNOSTIC TROUBLE CODE (DTC) TABLE
NOTE:
1 driving cycle: MIL lights up when DTC is detected in the first driving cycle.
2 driving cycles: MIL lights up when the same DTC is detected also in the next driving cycle after DTC is
detected and stored temporarily in the first driving cycle.
DTC
NO.
DETECTING ITEMDETECTING CONDITION
(DTC will set when detecting:)MIL
P0105Manifold absolute pressure
circuit malfunction
Low pressure-high vacuum-low voltage (or MAP
sensor circuit shorted to ground)
High pressure-low vacuum-high voltage (or MAP
sensor circuit open)
1 driving
cycle
P0110Intake air temp. circuit
malfunctionIntake air temp. circuit low input
Intake air temp. circuit high input1 driving
cycle
P0115Engine coolant temp. circuit
malfunctionEngine coolant temp. circuit low input
Engine coolant temp. circuit high input1 driving
cycle
P0120Throttle position circuit
malfunctionThrottle position circuit low input
Throttle position circuit high input1 driving
cycle
P0121Throttle position circuit
performance problemPoor performance of TP sensor2 driving
cycles
P0130HO2S circuit malfunction
(Sensor-1)
Min. output voltage of HO2S-higher than
specification
Max. output voltage of HO2S-lower than
specification
2 driving
cycles
P0133HO2S circuit slow response
(Sensor-1)Response time of HO2S-1 output voltage between
rich and lean is longer than specification.2 driving
cycles
P0134HO2S circuit no activity detected
(Sensor-1)Output voltage of HO2S-1 fails to go specification.
(or HO2S-1 circuit open or short)2 driving
cycles
P0135HO2S heater circuit malfunction
(Sensor-1)Terminal voltage is lower than specification at heater
OFF or it is higher at heater ON.2 driving
cycles
P0136HO2S circuit malfunction
(Sensor-2)Max. voltage of HO2S-2 is lower than specification
or its min. voltage is higher than specification2 driving
cycles
P0141HO2S heater circuit malfunction
(Sensor-2)Terminal voltage is lower than specification at heater
OFF or it is higher at heater ON. (or heater circuit or
short)2 driving
cycles
P0171Fuel system too lean
Short term fuel trim or total fuel trim (short and long
terms added) is larger than specification for specified
time or longer. (fuel trim toward rich side is large.)2 driving
cycles
P0172Fuel system too rich
Short term fuel trim or total fuel trim (short and long
term added) is smaller than specification for
specified time or longer. (fuel trim toward lean side is
large.)
2 driving
cycles
P0300
P0301
P0302
P0303Random misfire detected
Cylinder 1 misfire detected
Cylinder 2 misfire detected
Cylinder 3 misfire detectedMisfire of such level as to cause damage to three
way catalyst
MIL
flashing
during
misfire
detection
P0304
y
Cylinder 4 misfire detectedMisfire of such level as to deteriorate emission but
not to cause damage to three way catalyst2 driving
cycles
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
6-1-24 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
ConditionPossible CauseReferring Item
OverheatingInoperative thermostat
Poor water pump performance
Clogged or leaky radiator
Improper engine oil grade
Clogged oil filter or oil strainer
Poor oil pump performance
Faulty radiator fan control system
Dragging brakes
Slipping clutch
Blown cylinder head gasketThermostat in Section 6B
Water pump in Section 6B
Radiator in Section 6B
Engine oil and oil filter change in
Section 0B
Oil pressure check in Section 6A1
Oil pressure check in Section 6A1
Radiator fan control system in
Section 6E2
Trouble diagnosis in Section 5
Trouble diagnosis in Section 7C
Cylinder head in Section 6A1
Poor gasoline
mileageIgnition system out of order
Leaks or loose connection of high-tension cord
Faulty spark plug (improper gap, heavy deposits
and burned electrodes, etc.)
Engine and emission control system out of
order
Malfunctioning EGR valve
High idle speed
Poor performance of TP sensor, ECT sensor or
MAP sensor
Faulty EGR valve
Faulty fuel injector(s)
Faulty ECM (PCM)
Low compression
Others
Poor valve seating
Dragging brakes
Slipping clutch
Thermostat out of order
Improper tire pressure
High-tension cords in Section 6F1
Spark plugs in Section 6F1
EGR system in Section 6E2
Refer to item “Improper engine
idle speed” previously outlined
TP sensor, ECT sensor or MAP
sensor in Section 6E2
EGR system in Section 6E2
Diagnostic Flow Table B-1
Previously outlined
Valves inspection in Section 6A1
Trouble diagnosis in Section 5
Trouble diagnosis in Section 7C
Thermostat in Section 6B
Refer to Section 3F
Excessive engine
oil consumptionOil leakage
Blown cylinder head gasket
Leaky camshaft oil seals
Oil entering combustion chamber
Sticky piston ring
Worn piston and cylinder
Worn piston ring groove and ring
Improper location of piston ring gap
Worn or damaged valve stem seal
Worn valve stem
Cylinder head in Section 6A1
Camshaft in Section 6A1
Piston cleaning in Section 6A1
Pistons and cylinders inspection
in Section 6A1
Pistons inspection in Section 6A1
Pistons assembly in Section 6A1
Valves removal and installation in
Section 6A1
Valves inspection in Section 6A1
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-25
ConditionPossible CauseReferring Item
Engine hesitates
(Momentary lack of
response as
accelerator is
depressed.
Can occur at all
vehicle speeds.
Usually most severe
when first trying to
make vehicle move,
as from a stop sign.)Ignition system out of order
Spark plug faulty or plug gap out of adjustment
Leaky high-tension cord
Fuel system out of order
Fuel pressure out of specification
Engine and emission control system out of
order
Malfunctioning EGR valve
Poor performance of TP sensor, ECT sensor or
MAP sensor
Faulty fuel injector
Faulty ECM (PCM)
Engine overheating
Low compression
Spark plugs in Section 6F1
High-tension cords in Section 6F1
Diagnostic Flow Table B-3
EGR system in section 6E2
TP sensor, ECT sensor or MAP
sensor in Section 6E2
Diagnostic Flow Table B-1
Refer to “Overheating” section
Previously outlined
Surge
(Engine power
variation under
steady throttle or
cruise.
Feels like vehicle
speeds up and down
with no change in
accelerator pedal.)Ignition system out of order
Leaky or loosely connected high-tension cord
Faulty spark plug (excess carbon deposits,
improper gap, and burned electrodes, etc.)
Fuel system out of order
Variable fuel pressure
–Kinky or damaged fuel hose and lines
–Faulty fuel pump (clogged fuel filter)
Engine and emission control system out of
order
Malfunctioning EGR valve
Poor performance of MAP sensor
Faulty fuel injector
Faulty ECM (PCM)
High-tension cords in Section 6F1
Spark plugs in Section 6F1
Diagnostic Flow Table B-3
EGR system in Section 6E2
MAP sensor in Section 6E2
Diagnostic Flow Table B-1
Excessive
detonation
(Engine makes
continuously
sharp metallic
knocks that change
with throttle opening.
Sounds like pop corn
popping.)Engine overheating
Ignition system out of order
Faulty spark plug
Loose connection of high-tension cord
Fuel system out of order
Clogged fuel filter (faulty fuel pump) or fuel lines
Air inhaling from intake manifold or throttle body
gasket
Engine and emission control system out of
order
Malfunctioning EGR valve
Poor performance of ECT sensor or MAP sensor
Faulty fuel injector(s).
Faulty ECM (PCM)
Excessive combustion chamber depositsRefer to “Overheating” section
Spark plugs in Section 6F1
High-tension cords in Section 6F1
Diagnostic Flow Table B-1 or B-2
EGR system in Section 6E2
ECT sensor or MAP sensor in
Section 6E2
Diagnostic Flow Table B-1
Piston and cylinder head cleaning
in Section 6A1
6-1-26 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
ConditionPossible CauseReferring Item
Engine has no
powerIgnition system out of order
Faulty spark plug
Faulty ignition coil with ignitor
Leaks, loose connection or disconnection of
high-tension cord
Engine overheating
Fuel system out of order
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
Malfunctioning EGR valve
Maladjusted accelerator cable play
Poor performance of TP sensor, ECT sensor or
MAP sensor
Faulty fuel injector(s)
Faulty ECM (PCM)
Low compression
Others
Dragging brakes
Slipping clutch
Spark plugs in Section 6F1
Ignition coil in Section 6F1
High-tension cords in Section 6F1
Refer to “Overheating” section
Diagnostic Flow Table B-3
Diagnostic Flow Table B-2
EGR system inspection in Section
6E2
Accelerator cable play in Section
6E2
TP sensor, ECT sensor or MAP
sensor in Section 6E2
Diagnostic Flow Table B-1
Previously outlined
Trouble diagnosis in Section 5
Trouble diagnosis in Section 7C
ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13) 6-1-27
ConditionPossible CauseReferring Item
Improper engine
idling or engine
fails to idleIgnition system out of order
Faulty spark plug
Leaky or disconnected high-tension cord
Faulty ignition coil with ignitor
Fuel system out of order
Fuel pressure out of specification
Leaky manifold, throttle body, or cylinder head
gasket
Engine and emission control system out of
order
Malfunctioning EGR valve
Faulty idle air control system
Faulty evaporative emission control system
Faulty EGR system
Faulty fuel injector(s)
Poor performance of ECT sensor, TP sensor or
MAP sensor
Faulty ECM (PCM)
Engine overheating
Low compression
Others
Loose connection or disconnection of vacuum
hoses
Malfunctioning PCV valve
Spark plugs in Section 6F
High-tension cords in Section 6F
Ignition coil in Section 6F
Diagnostic Flow Table B-3
EGR system in Section 6E2
Diagnostic Flow Table B-4
EVAP control system in Section
6E2
EGR system in Section 6E2
Diagnostic Flow Table B-1
ECT sensor, TP sensor or MAP
sensor in Section 6E2
Refer to “Overheating” section
Previously outlined
PCV system in Section 6E2
6-1-28 ENGINE GENERAL INFORMATION AND DIAGNOSIS (SFI FOR G13)
ConditionPossible CauseReferring Item
Excessive
hydrocarbon (HC)
emission or carbon
monoxide (CO)Ignition system out of order
Faulty spark plug
Leaky or disconnected high-tension cord
Faulty ignition coil with ignitor
Low compression
Engine and emission control system out of
order
Lead contamination of three way catalytic
converter
Faulty evaporative emission control system
Fuel pressure out of specification
Closed loop system (A / F feed back
compensation) fails
–Faulty TP sensor
–Poor performance of ECT sensor or MAP
sensor
Faulty injector(s)
Faulty ECM (PCM)
Others
Engine not at normal operating temperature
Clogged air cleaner
Vacuum leaks
Spark plugs in Section 6F1
High-tension cords in Section 6F1
Ignition coil assembly in Section
6F1
Refer to “Low compression”
section
Check for absence of filler neck
restrictor
EVAP control system in Section
6E2
Diagnostic Flow Table B-3
TP sensor in Section 6E2
ECT sensor or MAP sensor in
Section 6E2
Diagnostic Flow Table B-1
Excessive nitrogen
oxides (NOx)
emissionIgnition system out of order
Improper ignition timing
Engine and emission control system out of
order
Lead contamination of catalytic converter
Faulty EGR system
Fuel pressure out of specification
Closed loop system (A / F feed back
compensation) fails
–Faulty TP sensor
–Poor performance of ECT sensor or MAP
sensor
Faulty injector(s)
Faulty ECM (PCM)
See section 6F1
Check for absence of filler neck
restrictor.
EGR system in Section 6E2
Diagnostic Flow Table B-3
TP sensor in Section 6E2
ECT sensor or MAP sensor in
Section 6E2
Diagnostic Flow Table B-1