2003 NISSAN ALMERA N16 mass air flow sensor

EC-404
[QG (WITH EURO-OBD)]
SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
PFP:00030
Fuel PressureEBS00KDN
Idle Speed and Ignition TimingEBS00KDO
*1: Under the following conditions:
●Air conditioner switch: OFF
●Electric load: OFF (Lights, heater fan & rear window defogger)
●Steering wheel: Kept in straight-ahead position
Calculated Load ValueEBS00KDP
Mass Air Flow SensorEBS00KDQ
*: Engine is warmed up to normal operating temperature and running under no-load.
Intake Air Temperature SensorEBS00KDR
Engine Coolant Temperature SensorEBS00KDS
Heated Oxygen Sensor 1 HeaterEBS00KDT
Heated Oxygen sensor 2 HeaterEBS00KDU
Crankshaft Position Sensor (POS)EBS00KDV
Refer to EC-238, "Component Inspection" .
Camshaft Position Sensor (PHASE)EBS00KDW
Refer to EC-244, "Component Inspection" .
Fuel pressure at idle
Approximately 350 kPa (3.5bar, 3.57kg/cm2 , 51psi)
Target idle speed
No-load*1 (in “P” or N” position)A/T: 800±50 rpm
M/T: 700±50 rpm
Air conditioner: ON In “P” or N” position 900 rpm or more
Ignition timingIn “P” or N” position A/T: 10°±5° BTDC
M/T: 8°±5° BTDC
Calculated load value % (Using CONSULT-II or GST)
At idle10 - 35
At 2,500 rpm10 - 35
Supply voltageBattery voltage (11 - 14V)
Output voltage at idle1.0 - 1.7*V
Mass air flow (Using CONSULT-II or GST)1.0 - 4.0 g·m/sec at idle*
5.0 - 10.0 g·m/sec at 2,500 rpm*
Temperature °C (°F) Resistance kΩ
25 (77)1.9 - 2.1
80 (176)0.31 - 0.37
Temperature °C (°F) Resistance kΩ
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
Resistance [at 20°C (68°F)] 8 - 10Ω
Resistance [at 25°C (77°F)] 2.3 - 4.3Ω

EC-410
[QG (WITHOUT EURO-OBD)]
PRECAUTIONS
●Do not disassemble ECM.
●If battery cable is disconnected, the memory will return to
the initial ECM values.
The ECM will now start to self-control at its initial values.
Engine operation can vary slightly when the cable is dis-
connected. However, this is not an indication of a malfunc-
tion. Do not replace parts because of a slight variation.
●When connecting ECM harness connector, fasten it
securely with a lever as far as it will go as shown at right.
●When connecting or disconnecting pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM
pin terminal, when connecting pin connectors.
●Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge)
voltage to develop in coil and condenser, thus resulting in
damage to ICs.
●Keep engine control system harness at least 10 cm (4 in)
away from adjacent harness, to prevent engine control sys-
tem malfunctions due to receiving external noise, degraded
operation of ICs, etc.
●Keep engine control system parts and harness dry.
●Before replacing ECM, perform “ECM Terminals and Refer-
ence Value” inspection and make sure ECM functions prop-
erly. Refer to EC-458, "
ECM Terminals and Reference Value"
.
●Handle mass air flow sensor carefully to avoid damage.
●Do not disassemble mass air flow sensor.
●Do not clean mass air flow sensor with any type of deter-
gent.
●Do not disassemble electric throttle control actuator.
●Even a slight leak in the air intake system can cause seri-
ous incidents.
●Do not shock or jar the camshaft position sensor (PHASE), crankshaft position sensor (POS).
PBIB1164E
MBIB0145E
PBIB0090E
MEF040D

ENGINE CONTROL SYSTEM
EC-417
[QG (WITHOUT EURO-OBD)]
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System ChartEBS00KEB
*1: This sensor is not used to control the engine system under normal conditions.
*2: The signals are sent to the ECM through CAN communication line.
*3: The output signals are sent from the ECM through CAN communication line.
Multiport Fuel Injection (MFI) SystemEBS00KEC
INPUT/OUTPUT SIGNAL CHART
*1: Under normal conditions, this sensor is not for engine control operation.
*2: This signal is sent to the ECM through CAN communication line.
*3: The 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). The amount of fuel injected is a program value in the
Input (Sensor) ECM Function Output (Actuator)
●Camshaft position sensor (PHASE)
●Crankshaft position sensor (POS)
●Mass air flow sensor
●Engine coolant temperature sensor
●Heated oxygen sensor 1
●Throttle position sensor
●Accelerator pedal position sensor
●Park/neutral position (PNP) switch
●Intake air temperature sensor
●Power steering pressure sensor
●Ignition switch
●Stop lamp switch
●Battery voltage
●Knock sensor
●Refrigerant pressure sensor
●Heated oxygen sensor 2*1
●TCM (Transmission control module)*2
●Air conditioner switch*2
●Vehicle speed signal*2
●Electrical load signal*2
Fuel injection & mixture ratio control Fuel injectors
Electronic ignition system Power transistor
Fuel pump control Fuel pump relay
On board diagnostic system
MI (On the instrument panel)
*3
Intake valve timing controlIntake valve timing control solenoid
valve
Heated oxygen sensor 1 heater control Heated oxygen sensor 1 heater
Heated oxygen sensor 2 heater control Heated oxygen sensor 2 heater
EVAP canister purge flow controlEVAP canister purge volume control
solenoid valve
Air conditioning cut control
Air conditioner relay
*3
Cooling fan control
Cooling fan relays*3
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed
*3 and piston position
Fuel injection & mix-
ture ratio controlFuel injectors Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Heated oxygen 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
Vehicle speed signal
*2Vehicle speed
Air conditioner switch
*2Air conditioner operation

EC-418
[QG (WITHOUT EURO-OBD)]
ENGINE CONTROL SYSTEM
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from the crankshaft position sensor (POS), camshaft position
sensor (PHASE) and the mass air flow sensor.
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.

●During warm-up
●When starting the engine
●During acceleration
●Hot-engine operation
●When selector lever is changed from “N” to “D” (A/T models)
●High-load, high-speed operation

●During deceleration
●During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system provides the best air-fuel mixture ratio for driveability and emission control.
The three way catalyst (manifold) can then better reduce CO, HC and NOx emissions. This system uses
heated oxygen sensor 1 in the exhaust manifold to monitor if the engine operation is rich or lean. The ECM
adjusts the injection pulse width according to the sensor voltage signal. For more information about heated
oxygen sensor 1, refer to EC-506
. 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 three way catalyst (manifold). Even if the switching
characteristics of heated oxygen 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 heated oxygen sensor 1 or its circuit
●Insufficient activation of heated oxygen sensor 1 at low engine coolant temperature
●High engine coolant temperature
●During warm-up
●After shifting from “N” to “D” (A/T models)
●When starting the engine
MIXTURE RATIO SELF-LEARNING CONTROL
The mixture ratio feedback control system monitors the mixture ratio signal transmitted from heated oxygen
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 basic mixture ratio is not necessarily controlled as orig-
PBIB0121E

ENGINE CONTROL SYSTEM
EC-419
[QG (WITHOUT EURO-OBD)]
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EC
inally designed. Both manufacturing differences (i.e., mass air flow sensor hot film) and characteristic changes
during operation (i.e., 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 compared 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 compensation used to maintain the mixture ratio at its theoretical
value. The signal from heated oxygen sensor 1 indicates whether the mixture ratio is RICH or LEAN compared
to the theoretical value. The signal then triggers a reduction 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 carried 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 cycle 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 four cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The four 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.
FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration or operation of the engine at excessively high speeds.
Electronic Ignition (EI) SystemEBS00KED
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: The ECM determines the start signal status by the signals of engine speed and battery voltage.
SEF337W
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed
*2 and piston position
Ignition timing control Power transistor 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
Vehicle speed signal*1Vehicle speed

TROUBLE DIAGNOSIS
EC-441
[QG (WITHOUT EURO-OBD)]
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Fail-safe ChartEBS00KET
●When the DTC listed below is detected, the ECM enters the fail-safe mode and the MI lights up.
Priority Detected items (DTC)
1
●U1000 U1001 CAN communication line
●P0102 P0103 Mass air flow sensor
●P0117 P0118 Engine coolant temperature sensor
●P0221 P0222 P0223 P1223 P1224 P1225 P1226 P1229 Throttle position sensor
●P0226 P0227 P0228 P1227 P1228 Accelerator pedal position sensor
●P0327 P0328 Knock sensor
●P0335 Crankshaft position sensor (POS)
●P0340 Camshaft position sensor (PHASE)
●P0605 ECM
●P1610-P1615 NATS
2
●P0132 P0134 Heated oxygen sensor 1
●P0138 Heated oxygen sensor 2
●P1065 ECM power supply
●P1122 Electric throttle control function
●P1124 P1126 P1128 Electric throttle control actuator
●P1805 Brake switch
3
●P1121 Electric throttle control actuator
●P1217 Engine over temperature (OVERHEAT)
DTC No. Detected items Engine operating condition in fail-safe mode
P0102
P0103Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0117
P0118Engine coolant tempera-
ture sensor circuitEngine coolant temperature will be determined by ECM based on the time after turning
ignition switch “ON” or “START”.
CONSULT-II displays the engine coolant temperature decided by ECM.
ConditionEngine coolant temperature decided (CONSULT-
II display)
Just as ignition switch is turned
ON or Start40°C (104°F)
More than approx. 4 minutes after
ignition ON or Start80°C (176°F)
Except as shown above40 - 80°C (104 - 176°F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cool-
ing fan operates while engine is running.
P0221
P0222
P0223
P1223
P1224Throttle 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 nor-
mal condition.
So, the acceleration will be poor.
P0226
P0227
P0228
P1227
P1228Accelerator pedal position
sensorThe 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 nor-
mal condition.
So, the acceleration will be poor.
P1121 Electric throttle control actu-
ator
(ECM detect 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.

EC-448
[QG (WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS
Symptom Matrix Chart
EBS00KEV
SYSTEM — BASIC ENGINE CONTROL SYSTEM
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 2EC-699
Fuel pressure regulator system334444444 4EC-427
Injector circuit 11232 22 2EC-693
Evaporative emission system 334444444 4EC-717
Air Positive crankcase ventilation sys-
tem334444444 41EC-720
Incorrect idle speed adjustment 33 1111 1EC-443
Electric throttle control actuator 112332222 2 2EC-575
,
EC-578
,
EC-585
,
EC-591
IgnitionIncorrect ignition timing adjustment33111 11 1EC-443
Ignition circuit 11222 22 2EC-660
Main power supply and ground circuit 22333 33 23EC-486
Mass air flow sensor circuit 11222 22 2EC-495
Engine coolant temperature sensor circuit 11222322312EC-501
Throttle position sensor circuit 12 22222 2EC-524
,
EC-530
,
EC-607
,
EC-613
,
EC-615
,
EC-624
Accelerator pedal position sensor circuit3212 2EC-536
,
EC-543
,
EC-617
Heated oxygen sensor 1 circuit 1232 22 2EC-506
,
EC-512
,
EC-647
Knock sensor circuit 2 2 3EC-550
Crankshaft position sensor (POS) circuit 2 2EC-554
Camshaft position sensor (PHASE) circuit 2 2EC-561
Vehicle speed signal circuit 2 3 3 3EC-677
Power steering pressure sensor circuit 2 3333EC-678

EC-450
[QG (WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS
Air Air duct
55555 5EM-14
Air cleanerEM-14
Air leakage from air duct
(Mass air flow sensor —electric
throttle control actuator)
5555EM-14
Electric throttle control actuatorEM-16
Air leakage from intake manifold/
Collector/GasketEM-16
Cranking Battery
111111 11SC-3
Alternator circuitSC-27
Starter circuit 3 SC-13
Signal plate/Flywheel/Drive plate 6EM-70
PNP switch
4AT- 11 6,
MT-21
Engine Cylinder head
55555 55 5EM-57
Cylinder head gasket 4 3
Cylinder block
66666 66 64
EM-70
Piston
Piston ring
Connecting rod
Bearing
Crankshaft
Va l v e
mecha-
nismTimin g c hain
55555 55 5EM-47
CamshaftEM-32
Intake valve timing controlEM-47
Intake valve
3EM-57
Exhaust valve
Exhaust Exhaust manifold/Tube/Muffler/
Gasket
55555 55 5EM-19
, FE-
26
Three way catalyst
Lubrica-
tionOil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery
55555 55 52EM-22
, LC-
5, LC-9,
LC-4
Oil level (Low)/Filthy oilLC-8 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