Ac control SUZUKI SWIFT 2005 2.G Service Service Manual

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-33
Scan Tool DataS7RS0B1104007
As the data values are standard values estimated on the basis of values obtained from the normally operating vehicles
by using a scan tool, use them as re ference values. Even when the vehicle is in good condition, 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 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 condition) as indicated by the scan tool.
Be sure to use the timing light to check the ignition timing.
NOTE
• There are two types of OBD system depending on the vehicle specification.
For details, refer to “Precaution on On-Board Diagnostic (OBD) System”.
• With the generic scan tool, only star (*) marked data in the following table can be read.
• When checking the data with the engine running at idle or racing, be sure to shift M/T gear to the neutral position and A/T gear to the “Park” position and pull the parking brake fully. Also, if nothing
or “no load” is indicated, turn O FF A/C (if equipped with A/C), all electric loads, P/S and all the other
necessary switches.

) P2122 Throttle/pedal position sensor/switch/“D” (main)
circuit low input
• ECM turns off throttle actuator control relay and throttle valve is fixed at the specified opening from
its completely closed position (default opening).
For details, refer to “Description of Electric
Throttle Body System”.
• ECM controls fuel cut at specified engine speed.
• ECM stops air/fuel ratio control.
)
P2123 Throttle/pedal position sensor/switch/“D” (main)
circuit high input
) P2127 Throttle/pedal position sensor/switch/“E” (sub)
circuit low input
) P2128 Throttle/pedal position sensor/switch/“E” (sub)
circuit high input
) P2135 Throttle/pedal position sensor/switch/“A”/“B”
(main) / (sub) voltage correction
) P2138 Throttle pedal position sensor/switch “D”/“E”
(main) / (sub) voltage correlation
) P2227 Barometric pressure sensor performance problem ECM controls actuators assuming that barometric
pressure is 101.33 kPa (762 mmHg).
DTC No. Detected item Fail-safe operation
Scan tool data
Vehicle condition Normal condition /
reference values
* ) COOLANT TEMP At specified idle speed after warming up 80 – 100 °C, 176 – 212 °F
* ) INTAKE AIR TEMP. At specifie d idle speed after warming up –5
°C (23 °F) + environmental
temp. to 40 °C (104 °F) +
environmental temp.
* ) ENGINE SPEED It idling with no load after warming upDesired idle speed ± 50 rpm
) INJ PULSE WIDTH At specified idle speed with no load after warming up
2.0 – 4.0 msec.
At 2500 r/min. with no load after warming up 2.0 – 3.6 msec.
) DESIRED IDLE It idling with radiator cooling fan stopped and all electrical
parts turned OFF after warming up, M/T at neutral 700 rpm
* ) SHORT FT B1 At specified idle speed after warming up –20 – +20%
* ) LONG FT B1 At specified idle speed after warming up –20 – +20%
) TOTAL FUEL TRIM
B1 At specified idle speed after warming up
–35 – +35%
* ) MAF At specified idle speed wit
h no load after warming up 1.0 – 4.0 g/s 0.14 – 0.52 lb/
min.
At 2500 r/min. with no load after warming up 4.0 – 12.0 g/s 0.53 – 1.58 lb/
min.
* ) CALC LOAD At specified idle speed with no load after warming up
18 – 28%
At 2500 r/min. with no load after warming up 13 – 23%
* )
THROTTLE
POSITION Ignition switch ON /
warmed up engine
stoppedAccelerator pedal released
0 – 5%
Accelerator pedal depressed
fully 90 – 100%

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-35
Scan Tool Data Definitions
COOLANT TEMP (ENGINE COOLANT
TEMPERATURE, °C, °F)
It is detected by engine coolant temp. sensor.
INTAKE AIR TEMP. ( °C, °F)
It is detected by intake air temp. sensor.
ENGINE SPEED (rpm)
It is computed by reference pulses from the camshaft
position sensor.
INJ PULSE WIDTH (FUEL INJECTION PULSE WIDTH,
msec.)
This parameter indicates time of the injector drive (valve
opening) pulse which is output from ECM (but injector
drive time of NO.1 cylinder fo r multiport fuel injection).
DESIRED IDLE (DESIRED IDLE SPEED, rpm)
The Desired Idle Speed is an ECM internal parameter
which indicates the ECM requested idle. If the engine is
not running, this number is not valid.
SHORT FT B1 (SHORT TERM FUEL TRIM, %)
Short term fuel trim valu e 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 indicates no correction, a value greater than 0
means an enrichment correction, and a value less than 0
implies an enleanment correction.
TOTAL FUEL TRIM B1 (%)
The value of Total Fuel Trim is obtained by calculating
based on values of Short Term Fuel Trim and Long Term
Fuel Trim. This value indica
tes how much correction is
necessary to keep the air/fuel mixture stoichiometrical.
MAF (MASS AIR FLOW RATE, g/s, lb/min.)
It represents total mass of air entering intake manifold
which is measured by mass air flow sensor.
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 × 100%
THROTTLE POS (ABSOLUTE THROTTLE POSITION,
%)
When throttle position sensor is at fully closed position,
throttle opening is indicated as 0 – 5% and 90 – 100%
full open position.
O2S SENSOR B1 S1 (HEA TED OXYGEN SENSOR-1,
V)
It indicates output voltage of HO2S-1 installed on
exhaust manifold (pre-catalyst).
)
TP SENSOR 2 VOLT Ignition switch ON after
warmed up engine Accelerator pedal released
1.4 – 1.8 V
Accelerator pedal depressed
fully 3.58 – 4.76 V
) APP SENSOR 1
VOLT Ignition switch ON after
warmed up engineAccelerator pedal released
0.5 – 0.9 V
Accelerator pedal depressed
fully 3.277 – 3.915 V
) APP SENSOR 2
VOLT Ignition switch ON after
warmed up engineAccelerator pedal released
1.3 – 1.7 V
Accelerator pedal depressed
fully 4.077 – 4.715 V
) ACCEL POSITION Ignition switch ON after
warmed up engine Accelerator pedal released
0 – 5%
Accelerator pedal depressed
fully 90 – 100%
) THROTTLE TARGET
POSI Ignition switch ON after
warmed up engineAccelerator pedal released
0 – 5%
Accelerator pedal depressed
fully 90 – 100%
) BATTERY
CURRENT At specified idle speed with no load after warming up
5.0 – 60.0 A
) GENERATOR CONT
DUTY (GENERATOR
CONTROL DUTY) At specified idle speed with no load after warming up
20.0 – 100.0%
) GENERATOR FIELD
DUTY (GENERATOR
FIELD COIL DUTY) At spe
cified idle speed with no load after warming up
20.0 – 100.0%
Scan tool data
Vehicle condition Normal condition /
reference values

Downloaded from www.Manualslib.com manuals search engine 1A-36 Engine General Information and Diagnosis:
O2S B1 S1 ACT (HEATED OXYGEN SENSOR-1,
ACTIVE / INACTIVE)
This parameter indicates activation condition of HO2S-1.
ACTIVE: Activating
INACTIVE: warming up or at stop
O2S SENSOR B1 S2 (HEATED OXYGEN SENSOR-2,
V)
It indicates output voltage of HO2S-2 installed on
exhaust pipe (post-catalyst). It is used to detect catalyst
deterioration.
O2S B1 S2 ACT (HEATED OXYGEN SENSOR-2,
ACTIVE / INACTIVE)
This parameter indicates acti vation condition of HO2S-2.
ACTIVE: Activating
INACTIVE: warming up or at stop
FUEL SYSTEM (FUEL SYSTEM STATUS)
Air/fuel ratio feedback loop status displayed as one of
the followings.
OPEN: Open-loop has not yet satisfied conditions to go
closed loop.
CLOSED: Closed-loop using oxygen sensor(s) as
feedback for fuel control.
OPEN-DRIVE COND: Open-loop due to driving
conditions (Power enrichment, etc.).
OPEN SYS FAULT: Open-loop due to detected system
fault.
MAP (MANIFOLD ABSOLUTE PRESSURE, in.Hg,
kPa)
This value indicates how much correction is necessary
to keep the air/fuel mixture stoichiometrical.
It is detected by manifold absolute pressure sensor.
BAROMETRIC PRESS (kPa, in.Hg)
This parameter represents a measurement of barometric
air pressure and is used for al titude correction of the fuel
injection quantity and IAC valve control.
STEP EGR FLOW DUTY (%)
This parameter indicates opening rate of EGR valve
which controls the amount of EGR flow.
FUEL CUT (ON/OFF)
ON: Fuel being cut (output signal to injector is stopped)
OFF: Fuel not being cut
A/C PRESSURE (A/C REFRIGERANT ABSOLUTE
PRESSURE, kPa)
This parameter indicates A/C refrigerant absolute
pressure calculated by ECM.
CLOSED THROTTLE PO S (CLOSED THROTTLE
POSITION, ON/OFF)
This parameter reads ON wh en throttle valve is fully
closed, or OFF when it is not fully closed. CANIST PRG DUTY (EVAP CANISTER PURGE FLOW
DUTY, %)
This parameter indicates valve ON (valve open) time
rate within a certain set cycle of EVAP canister purge
valve which controls the amount of EVAP purge.
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.
BATTERY VOLTAGE (V)
This parameter indicates battery positive voltage
inputted from main relay to ECM.
FUEL PUMP (ON/OFF)
ON is displayed when ECM activates the fuel pump via
the fuel pump relay switch.
ELECTRIC LOAD (ON/OFF)
ON: Headlight or small light ON signal inputted.
OFF: Above electric loads all turned OFF.
BRAKE SW (ON/OFF)
This parameter indicates the state of the brake switch.
RADIATOR COOLING FAN (RADIATOR COOLING
FAN CONTROL RELAY, ON/OFF)
ON: Command for radiator cooling fan control relay
operation being output.
OFF: Command for relay operation not being output.
BLOWER FAN (ON/OFF)
This parameter indicates the state of the blower fan
motor switch.
A/C SWITCH (ON/OFF)
ON: Command for A/C operatio n being output from ECM
to HVAC.
OFF: Command for A/C oper ation not being output.
A/C COMP RELAY (A/C COMPRESSOR RELAY, ON/
OFF)
This parameter indicates the state of the A/C switch.
VEHICLE SPEED (km/h, mph)
It is computed based on pulse signals from vehicle
speed sensor.
VVT GAP (TARGET-ACTUAL POSITION, °)
It is calculated using the formula: target valve timing
advance – actual valve timing advance.
TP SENSOR 1 VOLT (THROTTLE POSITION SENSOR
(MAIN) OUTPUT VOLTAGE, V)
The TP sensor (main) reading provides throttle valve
opening information in the form of voltage.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-37
TP SENSOR 2 VOLT (THROTTLE POSITION SENSOR
(SUB) OUTPUT VOLTAGE, V)
The TP sensor (sub) reading provides throttle valve
opening information in the form of voltage.
APP SENSOR 1 VOLT (ACCELERATOR PEDAL
POSITION (APP) SENSOR (MAIN) OUTPUT
VOLTAGE, V)
The APP sensor (main) read ing provides accelerator
pedal opening information in the form of voltage.
APP SENSOR 2 VOLT (ACCELERATOR PEDAL
POSITION (APP) SENSOR (S UB) OUTPUT VOLTAGE,
V)
The APP sensor (sub) reading provides accelerator
pedal opening information in the form of voltage.
ACCEL POSITION (ABSOLUTE ACCELERATOR
PEDAL POSITION, %)
When accelerator pedal is at fully released position,
accelerator pedal is indicated as 0 – 5% and 90 – 100%
fully depressed position. THROTTLE TARGET POSI (TARGET THROTTLE
VALVE POSITION, %)
Target throttle valve position is ECM internal parameter
which indicates the ECM requested throttle valve
position.
BATTERY CURRENT (A)
This parameter indicates elec
tric load value (current
consumption) that detected by electric load current
sensor.
GENERATOR CONT DUTY (GENERATOR CONTROL
DUTY, %)
This parameter indicates generator control duty ratio that
controls production electricity of generator by ECM.
100%: No limitation for the generating
0%: Maximum limitation for the generating
GENERATOR FIELD DUTY (GENERATOR FIELD
COIL DUTY, %)
This parameter indicates ope rating rate (status of
production electricity) for gen erator by field coil duty
ratio.
100%: maximum operation.
0%: minimum operation.
Visual InspectionS7RS0B1104008
Visually check the following parts and systems.
Inspection item Reference section
• Engine oil – level, leakage “Engine Oil and Filter Change in Section 0B”
• Engine coolant – level, leakage “Co olant Level Check in Section 1F”
• Fuel – level, leakage “Fuel Lines and Connections Inspection in Section 0B”
• Air cleaner element – dirt, clogging “Air Cleaner Filter Inspection in Section 0B”
• Battery – fluid level, corrosion of terminal “Battery Description in Section 1J”
• Water pump belt – tension damage “Accessory Drive Belt Inspection in Section 0B”
• Throttle valve – operating sound “Electric Throttle Body Assembly On-Vehicle Inspection in Section 1C”
• Vacuum hoses of air intake system – disconnection, looseness,
deterioration, bend “Vacuum Hose and Purge Valve Chamber
Inspection in Section 1B”
• Connectors of electric wire harness – disconnection, friction
• Fuses – burning
• Parts – installation, bolt – looseness
• Parts – deformation
• Other parts that can be checked visually
Also check the following items at engine start, if possible
• Malfunction indicator lamp – Operation “Malfunction Indicator Lamp (MIL) Check”
• Charge warning lamp – Operation “Genera tor Symptom Diagnosis in Section 1J”
• Engine oil pressure warning lamp – Operation “O il Pressure Switch Inspection in Section 9C”
• Engine coolant temp. meter – Operation “ECT Sensor Inspection in Section 1C”
• Fuel level meter – Operation “Fuel Level Sensor Inspection in Section 9C”
• Tachometer – Operation
• Abnormal air being inhaled from air intake system
• Exhaust system – leakage of exhaust gas, noise
• Other parts that can be checked visually

Downloaded from www.Manualslib.com manuals search engine 1A-38 Engine General Information and Diagnosis:
Engine Basic InspectionS7RS0B1104009
This check is very important for troubleshooting when ECM has detected no DTC and no abnormality has been found
in “Visual Inspection”.
Follow the flow carefully.Step Action Yes No 1 Was “Engine and Emission Control System Check”
performed? Go to Step 2. Go to “Engine and
Emission Control
System Check”.
2 Check battery voltage
Is it 11 V or more? Go to Step 3. Charge or replace
battery.
3 Is vehicle equipped with keyless start control system? Go to Step 4. Go to Step 5.
4 Check keyless start control system malfunction
1) Check keyless start control system referring to “Keyless
Start System Operation In spection in Section 10E”.
Is check result satisfactory? Go to Step 5. Keyless start control
system malfunction.
5 Is engine cranked? Go to Step 6. Go to “Cranking System
Symptom Diagnosis in
Section 1I”.
6 Does engine start? Go to Step 7. Go to Step 9.
7 Check idle speed
1) Warm up engine to normal operating temperature.
2) Shift transmission to neutral position for M/T (“P” position
for A/T).
3) Make sure that all electrical loads are switched off.
4) Check engine idle speed with scan tool.
Is it 650 – 800 r/min.? Go to Step 8. Go to “Engine Symptom
Diagnosis”.
I2RH01110005-01

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-39
8Check ignition timing
1) Using SUZUKI scan tool, select “Misc Test” mode on
SUZUKI scan tool and fix ignition timing to initial one.
2) Using timing light (1), check initial ignition timing. Special tool
(A): 09930–76420
Is it 5
°± 3° BTDC at specif ied idle speed? Go to “Engine Symptom
Diagnosis”.
Check ignition control
related parts referring to
“Ignition Timing
Inspection in Section
1H”.
9 Check immobilizer system malfunction
1) Check immobilizer indica tor lamp for flashing.
Is it flashing when ignition switch is turned to ON position? Go to “Diagnostic
Trouble Code (DTC)
Check in Section 10C”.
Go to Step 10.
10 Check fuel supply
1) Check to make sure that enough fuel is filled in fuel tank.
2) Turn ON ignition switch for 2 seconds and then OFF.
3) Repeat Step 2) a few times.
Is fuel pressure felt from fuel feed hose when ignition switch
is turned ON? Go to Step 12. Go to Step 11.
Step Action Yes No
I2RH01110006-01
1, (A)
10
0I3RB0A180004-01
I3RM0A110014-01

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-41
Engine Symptom DiagnosisS7RS0B1104010
Perform troubleshooting referring to the followings when ECM has detected no DTC and no abnormality has been
found in “Visual Inspection” and “Engine Basic Inspection”.
Condition Possible cause Correction / Reference Item
Hard starting (Engine
cranks OK) Faulty spark plug
“Spark Plug Inspection in Section 1H”
Leaky high-tension cord “High-Tension Cord Inspection in Section 1H”
Loose connection or disconnection of
high-tension cord(s) or lead wire(s) “High-Tension Cord Removal and Installation
in Section 1H”
Faulty ignition coil “Ignition Coil Assembly (Including ignitor)
Inspection in Section 1H”
Dirty or clogged fuel hose or pipe “Fuel Pressure Check”
Malfunctioning fuel pump “Fuel Pressure Check”
Air drawn in through intake manifold
gasket or throttle body gasket
Faulty electric throttle body assembly “Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly “APP Sensor Assembly Inspection in Section
1C”
Faulty ECT sensor or MAF sensor “ECT Sensor Inspection in Section 1C” or
“MAF and IAT Sensor Inspection in Section
1C”
Faulty ECM
Low compression “Compression Check in Section 1D”
Poor spark plug tightening or faulty
gasket “Spark Plug Removal and Installation in
Section 1H”
Compression leak from valve seat “Valves and Valve Guides Inspection in
Section 1D”
Sticky valve stem “Valves and Valve Guides Inspection in
Section 1D”
Weak or damaged valve springs “Valve Spring Inspection in Section 1D”
Compression leak at cylinder head
gasket “Cylinder Head Inspection in Section 1D”
Sticking or damaged piston ring “Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Worn piston, ring or cylinder “Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Malfunctioning PCV valve “PCV Valve Inspection in Section 1B”
Camshaft position control (VVT) system
out of order “Oil Control Valve Inspection in Section 1D”
Faulty EGR system “EGR System Inspection in Section 1B”
Low oil pressure Improper oil viscosity “Engine Oil and Filter Change in Section 0B”
Malfunctioning oil pressure switch “Oil Pressure Switch Inspection in Section 9C”
Clogged oil strainer “Oil Pan and Oil Pump Strainer Cleaning in
Section 1E”
Functional deterioration of oil pump “Oil Pump Inspection in Section 1E”
Worn oil pump relief valve “Oil Pump Inspection in Section 1E”
Excessive clearance in various sliding
parts
Engine noise – Valve
noise
NOTE
Before checking
mechanical noise, make
sure that:
• Specified spark plug is used.
• Specified fuel is used.

Improper valve lash “Camshaft, Tappet and Shim Inspection in
Section 1D”
Worn valve stem and guide “Valves and Valve Guides Inspection in
Section 1D”
Weak or broken valve spring “Valve Spring Inspection in Section 1D”
Warped or bent valve “Valves and Valve Guides Inspection in
Section 1D”

Downloaded from www.Manualslib.com manuals search engine 1A-42 Engine General Information and Diagnosis:
Engine noise – Piston,
ring and cylinder noise
NOTE
Before checking
mechanical noise, make
sure that:
• Specified spark plug is used.
• Specified fuel is used.

Worn piston, ring and cylinder bore “Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Engine noise –
Connecting rod noise
NOTE
Before checking
mechanical noise, make
sure that:
• Specified spark plug is used.
• Specified fuel is used.

Worn piston, ring and cylinder bore “Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Worn rod bearing “Crank Pin and Connecting Rod Bearings
Inspection in Section 1D”
Worn crank pin “Crank Pin and Connecting Rod Bearings
Inspection in Section 1D”
Loose connecting rod nuts “Pistons, Piston Rings, Connecting Rods and
Cylinders Removal and Installation in Section
1D”
Low oil pressure Condition “Low oil pressure”
Engine noise –
Crankshaft noise
NOTE
Before checking
mechanical noise, make
sure that:
• Specified spark plug is used.
• Specified fuel is used.

Low oil pressure Condition “Low oil pressure”
Worn bearing “Main Bearings Inspection in Section 1D”
Worn crankshaft journal “Crankshaft Inspection in Section 1D”
Loose bearing cap bolts “Main Bearings, Crankshaft and Cylinder Block
Removal and Installation in Section 1D”
Excessive crankshaft thrust play “Crankshaft Inspection in Section 1D”
Engine overheating Inoperative thermostat “Thermostat Inspection in Section 1F”
Poor water pump performance “Water Pump Inspection in Section 1F”
Clogged or leaky radiator “Radiator On-Vehicle Inspection and Cleaning
in Section 1F”
Improper engine oil grade “Engine Oil and Filter Change in Section 0B”
Clogged oil filter or oil strainer “Oil Pressure Check in Section 1E”
Poor oil pump performance “Oil Pressure Check in Section 1E”
Faulty radiator cooling fan control
system “Radiator Cooling Fan Low Speed Control
System Check” or “Rad
iator Cooling Fan High
Speed Control System Check”
Dragging brakes Condition “Dragging brakes” in “Brakes
Symptom Diagnosis in Section 4A”
Slipping clutch Condition “Slipping clutch” in “Clutch System
Symptom Diagnosis in Section 5C”
Blown cylinder head gasket “Cylinder Head Inspection in Section 1D”
Air mixed in cooling system
Condition Possible cause Correction / Reference Item

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-43
Poor gasoline mileageLeaks or loose connection of high-
tension cord “High-Tension Cord Removal and Installation
in Section 1H”
Faulty spark plug (improper gap, heavy
deposits and burned electrodes, etc.) “Spark Plug Inspection in Section 1H”
Malfunctioning EGR valve “EGR Valve Inspection in Section 1B”
High idle speed Condition “Improper engine idling or engine
fails to idle”
Poor performance of ECT sensor or
MAF sensor “ECT Sensor Inspection in Section 1C” or
“MAF and IAT Sensor Inspection in Section
1C”
Faulty electric throttle body assembly “Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly “APP Sensor Assembly Inspection in Section
1C”
Faulty fuel injector(s) “Fuel Injector Circuit Check”
Faulty ECM
Low compression “Compression Check in Section 1D”
Poor valve seating “Valves and Valve Guides Inspection in
Section 1D”
Dragging brakes Condition “Dragging brakes” in “Brakes
Symptom Diagnosis in Section 4A”
Slipping clutch Condition “Slipping clutch” in “Clutch System
Symptom Diagnosis in Section 5C”
Thermostat out of order “Thermostat Inspection in Section 1F”
Improper tire pressure “Tires Description in Section 2D”
Camshaft position control (VVT) system
out of order “Oil Control Valve Inspection in Section 1D”
Excessive engine oil
consumption – Oil
leakage Blown cylinder head gasket
“Cylinder Head Inspection in Section 1D”
Leaky camshaft oil seals “Camshaft, Tappet and Shim Inspection in
Section 1D”
Excessive engine oil
consumption – Oil
entering combustion
chamber Sticky piston ring
“Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Worn piston and cylinder “Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Worn piston ring groove and ring “Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Improper location of piston ring gap “Pistons, Piston Rings, Connecting Rods and
Cylinders Disassembly and Assembly in
Section 1D”
Worn or damaged valve stem seal “Valves and Valve Guides Inspection in
Section 1D”
Worn valve stem “Valves and Valve Guides Inspection in
Section 1D”
Condition Possible cause Correction / Reference Item

Downloaded from www.Manualslib.com manuals search engine 1A-44 Engine General Information and Diagnosis:
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.Spark plug faulty
“Spark Plug Inspection in Section 1H”
Leaky high-tension cord “High-Tension Cord Inspection in Section 1H”
Fuel pressure out of specification “Fuel Pressure Check”
Malfunctioning EGR valve “EGR Valve Inspection in Section 1B”
Poor performance of ECT sensor or
MAF sensor “ECT Sensor Inspection in Section 1C” or
“MAF and IAT Sensor Inspection in Section
1C”
Faulty electric throttle body assembly “Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly “APP Sensor Assembly Inspection in Section
1C”
Faulty fuel injector “Fuel Injector Circuit Check”
Faulty ECM
Engine overheating Condition “Engine overheating”
Low compression “Compression Check in Section 1D”
Camshaft position control (VVT) system
out of order “Oil Control Valve Inspection in Section 1D”
Surge – Engine power
variation under steady
throttle or cruise. Feels
like vehicle speeds up
and down with no change
in accelerator pedal. Leaky or loosely connected high-tension
cord
“High-Tension Cord Removal and Installation
in Section 1H”
Faulty spark plug (excess carbon
deposits, improper gap, burned
electrodes, etc.) “Spark Plug Inspection in Section 1H”
Variable fuel pressure “Fuel Pressure Check”
Kinky or damaged fuel hose and lines
Faulty fuel pump (clogged fuel filter)
Malfunctioning EGR valve “EGR Valve Inspection in Section 1B”
Poor performance of MAF sensor “MAF and IAT Sensor Inspection in Section
1C”
Faulty fuel injector “Fuel Injector Circuit Check”
Faulty electric throttle body assembly “Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly “APP Sensor Assembly Inspection in Section
1C”
Faulty ECM
Excessive detonation –
Engine makes
continuously sharp
metallic knocks that
change with throttle
opening. Sounds like pop
corn popping. Faulty spark plug
“Spark Plug Inspection in Section 1H”
Loose connection of high-tension cord “High-Tension Cord Removal and Installation
in Section 1H”
Engine overheating Condition “Engine overheating”
Clogged fuel filter (faulty fuel pump) or
fuel lines “Fuel Pressure Check” or “Fuel Pump and Its
Circuit Check”
Air drawn in through intake manifold or
throttle body gasket
Malfunctioning EGR valve “EGR Valve Inspection in Section 1B”
Poor performance of knock sensor, ECT
sensor or MAF sensor “DTC P0327 / P0328: Knock Sensor 1 Circuit
Low / High”, “ECT Sensor Inspection in
Section 1C” or “MAF and IAT Sensor
Inspection in Section 1C”
Faulty fuel injector(s) “Fuel Injector Circuit Check”
Faulty ECM
Excessive combustion chamber
deposits “Cylinders, Pistons and Piston Rings
Inspection in Section 1D” and/or “Piston Pins
and Connecting Rods In
spection in Section
1D”
Camshaft position control (VVT) system
out of order “Oil Control Valve Inspection in Section 1D”
Condition Possible cause Correction / Reference Item