Coolant Temperature Sensor INFINITI FX35 2008 User Guide

EC-16
Description ...........................................................1182
CONSULT-III Reference Value in Data Monitor
Mode ....................................................................
1182
Wiring Diagram ....................................................1183
Diagnosis Procedure ...........................................1183
Component Inspection .........................................1185
VARIABLE INDUCTION AIR CONTROL SYS-
TEM (VIAS) .....................................................
1187
Description ...........................................................1187
CONSULT-III Reference Va lue in Data Monitor
Mode ....................................................................
1188
Wiring Diagram ....................................................1189
Diagnosis Procedure ...........................................1190
Component Inspection .........................................1193
Removal and Installation .....................................1193
MIL AND DATA LINK CONNECTOR .............1194
Wiring Diagram ....................................................1194
SERVICE DATA AND SPECIFICATIONS
(SDS) ..............................................................
1196
Fuel Pressure .......................................................1196
Idle Speed and Ignition Timing ............................1196
Calculated Load Value .........................................1196
Mass Air Flow Sensor ..........................................1196
Intake Air Temperature Sensor ............................1196
Engine Coolant Temperature Sensor ..................1196
Fuel Tank Temperature Sensor ...........................1196
Crankshaft Position Sensor (POS) ......................1197
Camshaft Position Sensor (PHASE) ....................1197
A/F Sensor 1 Heater ............................................1197
Heated Oxygen sensor 2 Heater .........................1197
Throttle Control Motor ..........................................1197
Fuel Injector .........................................................1197
Fuel Pump ............................................................1197
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EC-32
< SERVICE INFORMATION >[VQ35DE]
ENGINE CONTROL SYSTEM
*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is
determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). T he amount of fuel injected is a program value in the
ECM memory. The program value is preset by engi ne operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from both the crankshaft position sensor and the mass air
flow sensor.
VARIOUS FUEL INJECTION I NCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compens ated to improve engine performance under various operat-
ing conditions as listed below.
<Fuel increase> During warm-up
 When starting the engine
 During acceleration
 Hot-engine operation
 When selector lever is changed from N to D
 High-load, high-speed operation
<Fuel decrease> During deceleration
 During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system prov ides the best air-fuel mixture ratio for driveability and emission control.
The three way catalyst 1 can then better reduce CO, HC and NOx emissions. This system uses air fuel ratio
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*
3
Piston position
Fuel injection
& mixture ratio
controlFuel injector
Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Knock sensor Engine knocking condition
Battery
Battery voltage*
3
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
Air conditioner switch Air conditioner operation*
2
Wheel sensorVehicle speed*2
PBIB3020E
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ENGINE CONTROL SYSTEMEC-33
< SERVICE INFORMATION > [VQ35DE]
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(A/F) sensor 1 in the exhaust manifold to monitor
whether the engine operation is rich or lean. The ECM
adjusts the injection pulse width according to the sensor voltage signal. For more information about air fuel
ratio (A/F) sensor 1, refer to EC-220
. This maintains the mixture ratio within the range of stoichiometric (ideal
air-fuel mixture).
This stage is referred to as the closed loop control condition.
Heated oxygen sensor 2 is located downstream of the thr ee way catalyst 1. Even if the switching characteris-
tics of air fuel ratio (A/F) sensor 1 shift, the air-fuel ratio is controlled to stoichiometric by the signal from
heated oxygen sensor 2.
Open Loop Control
The open loop system condition refers to when the ECM detects any of the following conditions. Feedback
control stops in order to maintain stabilized fuel combustion.
 Deceleration and acceleration
 High-load, high-speed operation
 Malfunction of air fuel ratio (A/F) sensor 1 or its circuit
 Insufficient activation of air fuel ratio (A /F) sensor 1 at low engine coolant temperature
 High engine coolant temperature
 During warm-up
 After shifting from N to D
 When starting the engine
MIXTURE RATIO SELF-LEARNING CONTROL
The mixture ratio feedback control system monitors the mixture ratio signal transmitted from air fuel ratio (A/F)
sensor 1. This feedback signal is then sent to the ECM. The ECM controls the basic mixture ratio as close to
the theoretical mixture ratio as possible. However, the bas ic mixture ratio is not necessarily controlled as orig-
inally designed. Both manufacturing differences (i.e., mass air flow sensor hot wire) and characteristic
changes during operation (i.e., fuel injector clogging) directly affect mixture ratio.
Accordingly, the difference between the basic and theoretical mixture ratios is monitored in this system. This is
then computed in terms of “injection pulse duration” to automatically compensate for the difference between
the two ratios.
“Fuel trim” refers to the feedback compensation value co mpared against the basic injection duration. Fuel trim
includes short term fuel trim and long term fuel trim.
“Short term fuel trim” is the short-term fuel compensati on used to maintain the mixture ratio at its theoretical
value. The signal from air fuel ratio (A/F) sensor 1 i ndicates whether the mixture ratio is RICH or LEAN com-
pared to the theoretical value. The signal then triggers a r eduction in fuel volume if the mixture ratio is rich, and
an increase in fuel volume if it is lean.
“Long term fuel trim” is overall fuel compensation ca rried out long-term to compensate for continual deviation
of the short term fuel trim from the central value. Such deviation will occur due to individual engine differences,
wear over time and changes in the usage environment.
FUEL INJECTION TIMING
Two types of systems are used.
Sequential Multiport Fuel Injection System
Fuel is injected into each cylinder during each engine cycl e according to the firing order. This system is used
when the engine is running.
Simultaneous Multiport Fuel Injection System
Fuel is injected simultaneously into all six cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The six fuel injectors will then receive the signals two times for each engine cycle.
This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.
SEF179U
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EC-34
< SERVICE INFORMATION >[VQ35DE]
ENGINE CONTROL SYSTEM
FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration,
operation of the engine at excessively high speeds or oper-
ation of the vehicle at excessively high speeds.
Electronic Ignition (EI) SystemINFOID:0000000001325897
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
Firing order: 1 - 2 - 3 - 4 - 5 - 6
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the
engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injection pulse width and camshaft position sensor (PHASE) sig-
nal. Computing this information, ignition si gnals are transmitted to the power transistor.
During the following conditions, the ignition timing is re vised by the ECM according to the other data stored in
the ECM.
 At starting
 During warm-up
 At idle
 At low battery voltage
 During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
Fuel Cut Control (at No Load and High Engine Speed)INFOID:0000000001325898
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*
2
Piston position
Ignition timing
controlPower transistor
Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Knock sensor Engine knocking
Park/neutral position (PNP) switch Gear position
Battery
Battery voltage*
2
Wheel sensor
Vehicle speed*1
Sensor Input Signal to ECM ECM function Actuator
Park/neutral position (P NP) switch Neutral position
Fuel cut control Fuel injector
Accelerator pedal position sensor Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)
Engine speed
Wheel sensor Vehicle speed*
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EC-36
< SERVICE INFORMATION >[VQ35DE]
AIR CONDITIONING CUT CONTROL
AIR CONDITIONING CUT CONTROL
Input/Output Signal ChartINFOID:0000000001325899
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
System DescriptionINFOID:0000000001325900
This system improves engine operati
on when the air conditioner is used.
Under the following conditions, the air conditioner is turned OFF.
 When the accelerator pedal is fully depressed.
 When cranking the engine.
 At high engine speeds.
 When the engine coolant temperature becomes excessively high.
 When operating power steering during low engine speed or low vehicle speed.
 When engine speed is excessively low.
 When refrigerant pressure is excessively low or high.
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch Air conditioner ON signal*
1
Air conditioner
cut controlAir conditio
ner relay
Accelerator pedal position sensor Accelerator pedal position
Throttle position sensor Throttle position
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)
Engine speed*2
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage*
2
Refrigerant pressure sensor Refrigerant pressure
Power steering pressure sensor Power steering operation
Wheel sensorVehicle speed*
1
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AUTOMATIC SPEED CONTROL DEVICE (ASCD)EC-37
< SERVICE INFORMATION > [VQ35DE]
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AUTOMATIC SPEED CONTROL DEVICE (ASCD)
System DescriptionINFOID:0000000001325901
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
BASIC ASCD SYSTEM
Refer to Owner's Manual for ASCD operating instructions.
Automatic Speed Control Device (ASCD) allows a dr
iver to keep vehicle at predetermined constant speed
without depressing accelerator pedal. Driver can set vehicle speed in advance between approximately 40 km/
h (25 MPH) and 144 km/h (89 MPH).
ECM controls throttle angle of electric thro ttle control actuator to regulate engine speed.
Operation status of ASCD is indicated by CRUISE i ndicator and SET indicator in combination meter. If any
malfunction occurs in ASCD system, it automatically deactivates control.
NOTE:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.
SET OPERATION
Press MAIN switch. (The CRUISE indicator in combination meter illuminates.)
When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89
MPH), press SET/COAST switch. (Then SET indi cator in combination meter illuminates.)
ACCELERATOR OPERATION
If the RESUME/ACCELERATE switch is pressed during cruise control driving, increase the vehicle speed until
the switch is released or vehicle speed reac hes maximum speed controlled by the system.
And then ASCD will keep the new set speed.
CANCEL OPERATION
When any of following conditions exist, cruise operation will be canceled.
 CANCEL switch is pressed
 More than 2 switches at ASCD steering switch are pressed at the same time (Set speed will be cleared)
 Brake pedal is depressed
 Selector lever is changed to N, P, R position
 Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed
 VDC/TCS system is operated
When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform
the driver by blinking indicator lamp.
 Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE lamp may
blink slowly.
When the engine coolant temperature decreases to t he normal operating temperature, CRUISE lamp will
stop blinking and the cruise operation will be able to work by depressing SET/COAST switch or RESUME/
ACCELERATE switch.
 Malfunction for some self-diagnoses regarding ASCD control: SET lamp will blink quickly.
If MAIN switch is turned to OFF during ASCD is activated, all of ASCD operations will be canceled and vehicle
speed memory will be erased.
COAST OPERATION
When the SET/COAST switch is pressed during cruise control driving, decrease vehicle set speed until the
switch is released. And then ASCD will keep the new set speed.
RESUME OPERATION
Sensor Input signal to ECM ECM function Actuator
ASCD brake switch Brake pedal operation
ASCD vehicle speed controlElectric throttle control
actuator
Stop lamp switch Brake pedal operation
ASCD steering switch ASCD steering switch operation
Park/neutral position (PNP) switch Gear position
Wheel sensor. Vehicle speed*
TCM Powertrain revolution*
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BASIC SERVICE PROCEDUREEC-85
< SERVICE INFORMATION > [VQ35DE]
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4. Follow the instruction of CONSULT-III display.
Accelerator Pedal Releas
ed Position LearningINFOID:0000000001325923
DESCRIPTION
Accelerator Pedal Released Position Learning is an operation to learn the fully released position of the accel-
erator pedal by monitoring the accelerator pedal posit ion sensor output signal. It must be performed each time
harness connector of accelerator pedal position sensor or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON and wait at least 2 seconds.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and wait at least 2 seconds.
5. Turn ignition switch OFF and wait at least 10 seconds.
Throttle Valve Closed Position LearningINFOID:0000000001325924
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to l earn the fully closed position of the throttle valve by
monitoring the throttle position sensor output signal . It must be performed each time harness connector of
electric throttle control ac tuator or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume LearningINFOID:0000000001325925
DESCRIPTION
Idle Air Volume Learning is an operation to learn the idle air volume that keeps each engine within the specific
range. It must be performed under any of the following conditions:
 Each time electric throttle control actuator or ECM is replaced.
 Idle speed or ignition timing is out of specification.
PREPARATION
Before performing Idle Air Volume Learning, make sure that all of the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are missed for even a moment.
 Battery voltage: More than 12.9V (At idle)
 Engine coolant temperature: 70 - 100 °C (158 - 212 °F)
 Park/neutral position switch: ON
 Electric load switch: OFF (Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is
started the headlamp will not be illuminated.
 Steering wheel: Neutral (Straight-ahead position)
 Vehicle speed: Stopped
 Transmission: Warmed-up
- For models with CONSULT-III, drive vehicle until “A TF TEMP SE 1” in “DATA MONITOR” mode of “A/T” sys-
tem indicates less than 0.9V.
- For models without CONSULT-III, drive vehicle for 10 minutes.
OPERATION PROCEDURE
With CONSULT-III
1. Perform EC-85, "Accelerator Pedal Released Position Learning".
2. Perform EC-85, "
Throttle Valve Closed Position Learning".
3. Start engine and warm it up to normal operating temperature.
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EC-94
< SERVICE INFORMATION >[VQ35DE]
TROUBLE DIAGNOSIS

If DTC U1000 or U1001 is displayed with other DT C, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-146
.
 If DTC U1010 is displayed with other DTC, fi rst perform the trouble diagnosis for DTC U1010.
Refer to EC-148
.
*: Models with ICC.Priority Detected items (DTC)
1  U1000 U1001 CAN communication line  U1010 CAN communication
 P0101 P0102 P0103 Mass air flow sensor
 P0112 P0113 P0127 Intake air temperature sensor
 P0117 P0118 P0125 Engine coolant temperature sensor
 P0128 Thermostat function
 P0122 P0123 P0222 P0223 P1225 P1226 P2135 Throttle position sensor
 P0181 P0182 P0183 Fuel tank temperature sensor
 P0327 P0328 Knock sensor
 P0335 Crankshaft position sensor (POS)
 P0340 P0345 Camshaft position sensor (PHASE)
 P0460 P0461 P0462 P0463 Fuel level sensor
 P0500 Vehicle speed sensor
 P0605 ECM
 P0643 Sensor power supply
 P0700 TCM
 P0705 Park/neutral position (PNP) switch
 P0850 Park/neutral position (PNP) switch
 P1610 - P1615 NATS
 P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor
2  P0031 P0032 P0051 P0052 Air fuel ratio (A/F) sensor 1 heater  P0037 P0038 P0057 P0058 Heated oxygen sensor 2 heater
 P0075 P0081 Intake valve timing control solenoid valve
 P0130 P0131 P0132 P0133 P0150 P0151 P0152 P0153 P2A00 P2A03 Air fuel ratio (A/F) sensor 1
 P0137 P0138 P0139 P0157 P0158 P0159 Heated oxygen sensor 2
 P0441 EVAP control system purge flow monitoring
 P0443 P0444 P0445 EVAP canister purge volume control solenoid valve
 P0447 P0448 EVAP canister vent control valve
 P0451 P0452 P0453 EVAP control system pressure sensor
 P0550 Power steering pressure sensor
 P0603 ECM power supply
 P0710 P0717 P0720 P0731 P0732 P0733 P0734 P0735 P0740 P0744 P0745 P1730 P1752 P1757 P1762 P1767
P1772 P1774 A/T related sensors, solenoid valves and switches
 P1217 Engine over temperature (OVERHEAT)
 P1805 Brake switch
 P2100 P2103 P2118 Electric throttle control actuator
 P2101 Electric throttle control function
3  P0011 P0021 Intake valve timing control  P0171 P0172 P0174 P0175 Fuel injection system function
 P0300 - P0306 Misfire
 P0420 P0430 Three way catalyst function
 P0442 EVAP control system (SMALL LEAK)
 P0455 EVAP control system (GROSS LEAK)
 P0456 EVAP control sys tem (VERY SMALL LEAK)
 P0506 P0507 Idle speed control system
 P1148 P1168 Closed loop control
 P1211 TCS control unit
 P1212 TCS communication line
 P1421 COLD START CONTROL
 P1564 ICC steering switch/ASCD steering switch
 P1568 ICC command valve*
 P1572 ICC brake switch/ASCD brake switch
 P1574 ICC vehicle speed sensor/ASCD vehicle speed sensor
 P1715 Turbine revolution sensor
 P2119 Electric throttle control actuator
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TROUBLE DIAGNOSISEC-95
< SERVICE INFORMATION > [VQ35DE]
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Fail-Safe ChartINFOID:0000000001325929
When the DTC listed below is detected, the EC
M enters fail-safe mode and the MIL lights up.
 When there is an open circuit on MIL circuit, the ECM c annot warn the driver by MIL lighting up when there
is malfunction on engine control system.
Therefore, when electrical controlled throttle and pa rt of ECM related diagnoses are continuously detected
as NG for 5 trips, ECM warns the driver that engi ne control system malfunctions and MIL circuit is open by
means of operating fail-safe function.
The fail-safe function also operates when above diagnos es except MIL circuit are detected and demands the
driver to repair the malfunction.
DTC No. Detected items Engine operating condition in fail-safe mode
P0102
P0103 Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0117
P0118 Engine coolant tempera-
ture sensor circuit Engine coolant temperature will be determined by ECM based on the following condition.
CONSULT-III displays the engine coolant temperature decided by ECM.
Condition Engine coolant temperature decided
(CONSULT-III display)
Just as ignition switch is turned ON
or START 40
°C (104 °F)
Approx. 4 minutes or more after
engine starting. 80
°C (176 °F)
Except as shown above 40 - 80
°C (104 - 176 °F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling
fan operates while engine is running.
P0122
P0123
P0222
P0223
P2135 Throttle position sensor The ECM controls the electric throttle control actuator in regulating the throttle opening in
order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal
condition.
So, the acceleration will be poor.
P0643 Sensor power supply ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
P2100
P2103 Throttle control motor relay ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P2101 Electric th rottle control
function ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P2118 Throttle control motor ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
P2119 Electric thro ttle control ac-
tuator (When electric throttle control actuator does not function properly due to the return spring
malfunction:)
ECM controls the electric throttle actuator by regulating the throttle opening around the
idle position. The engine speed will not rise more than 2,000 rpm.
(When throttle valve opening angle in fail-safe mode is not in specified range:)
ECM controls the electric throttle control actuator by regulating the throttle opening to 20
degrees or less.
(When ECM detects the throttle valve is stuck open:)
While the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops, the
engine stalls.
The engine can restart in N or P position, and engine speed will not exceed 1,000 rpm or
more.
P2122
P2123
P2127
P2128
P2138 Accelerator pedal position
sensor
The ECM controls the electric throttle control actuator in regulating the throttle opening in
order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal
condition.
So, the acceleration will be poor.
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EC-96
< SERVICE INFORMATION >[VQ35DE]
TROUBLE DIAGNOSIS
Symptom Matrix Chart
INFOID:0000000001325930
SYSTEM — BASIC ENGINE CONTROL SYSTEM
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel pump circuit 11232 22 3 2 EC-558
Fuel pressure regulator system 334444444 4EC-87
Fuel injector circuit 11232 22 2EC-552
Evaporative emission system 334444444 4EC-40
Air Positive crankcase ventilation sys-
tem 334444444 41
EC-51
Incorrect idle speed adjustment 1 1 1 1 1 EC-80
Electric throttle control actuator 112332222 2 2EC-494,
EC-504
IgnitionIncorrect ignition timing adjustment33111 11 1 EC-80
Ignition circuit 11222 22 2EC-569
Power supply and ground circuit 22333 33 23 EC-140
Mass air flow sensor circuit
1
12 2
222 2 EC-175,
EC-182
Engine coolant temperature sensor circuit
333
EC-193,
EC-204
Air fuel ratio (A/F) sensor EC-220
EC-220
EC-228
EC-236
EC-532
Throttle position sensor circuit
22EC-198
,
EC-302
,
EC-447
,
EC-449
,
EC-518
Accelerator pedal position sensor circuit 3 2 1 EC-424
,
EC-506
,
EC-512
,
EC-524
Knock sensor circuit 2 3 EC-315
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