NISSAN ALMERA 2001 Service Manual
Page 741 of 2898
SEF706Y
Engine Fuel & Emission Control System=NJEC0004+Always use a 12 volt battery as power source.
+Do not attempt to disconnect battery cables while engine
is running.
+Before connecting or disconnecting the ECM harness
connector, turn ignition switch OFF and disconnect nega-
tive battery terminal. Failure to do so may damage the
ECM because battery voltage is applied to ECM even if
ignition switch is turned off.
SEF707Y
+Do not disassemble ECM.
+If a battery terminal is disconnected, the memory will
return to the ECM value.
The ECM will now start to self-control at its initial value.
Engine operation can vary slightly when the terminal is
disconnected. However, this is not an indication of a prob-
lem. Do not replace parts because of a slight variation.
SEF908W
+When connecting or disconnecting ECM harness
connector, use lever as shown.
When connecting, fasten connector securely with lever
moved until it stops.
SEF291H
+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 terminals 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 ECM harness at least 10 cm (4 in) away from adja-
cent harness, to prevent an ECM system malfunctions due
to receiving external noise, degraded operation of ICs, etc.
+Keep ECM parts and harness dry.
PRECAUTIONSQG
Engine Fuel & Emission Control System
EC-17
Page 742 of 2898
MEF040D
+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 IAC valve-AAC valve.
+Even a slight leak in the air intake system can cause seri-
ous problems.
+Do not shock or jar the camshaft position sensor and
crankshaft position sensor.
+Before replacing ECM, perform refer to ªECM Terminals
and Reference Valueº inspection and make sure ECM
functions properly, EC-164.
SAT652J
+After performing each TROUBLE DIAGNOSIS, perform
ªDTC Confirmation Procedureº or ªOverall Function
Checkº.
The DTC should not be displayed in the ªDTC Confirma-
tion Procedureº if the repair is completed. The ªOverall
Function Checkº should be a good result if the repair is
completed.
SEF348N
+When measuring ECM signals with a circuit tester, never
allow the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.
+Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the
ECM's transistor. Use a ground other than ECM terminals,
such as the ground.
PRECAUTIONSQG
Engine Fuel & Emission Control System (Cont'd)
EC-18
Page 743 of 2898
SEF605X
+Do not operate fuel pump when there is no fuel in lines.
+Tighten fuel hose clamps to the specified torque.
SEF709Y
+Do not depress accelerator pedal when starting.
+Immediately after starting, do not rev up engine unneces-
sarily.
+Do not rev up engine just prior to shutdown.
SEF708Y
+When installing C.B. ham radio or a mobile phone, be sure
to observe the following as it may adversely affect elec-
tronic control systems depending on installation location.
1)Keep the antenna as far as possible from the electronic
control units.
2)Keep the antenna feeder line more than 20 cm (8 in) away
from the harness of electronic controls.
Do not let them run parallel for a long distance.
3)Adjust the antenna and feeder line so that the standing-
wave ratio can be kept smaller.
4)Be sure to ground the radio to vehicle body.
Wiring Diagrams and Trouble DiagnosisNJEC0006When you read Wiring diagrams, refer to the following:
+GI-11, ªHOW TO READ WIRING DIAGRAMSº
+EL-10, ªPOWER SUPPLY ROUTINGº for power distribution
circuit
When you perform trouble diagnosis, refer to the following:
+GI-31, ªHOW TO FOLLOW TEST GROUP IN TROUBLE
DIAGNOSISº
+GI-21, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR
AN ELECTRICAL INCIDENTº
PRECAUTIONSQG
Engine Fuel & Emission Control System (Cont'd)
EC-19
Page 744 of 2898
Special Service ToolsNJEC0007
Tool number
Tool nameDescription
KV10117100
Heated oxygen sensor
wrench
NT379
Loosening or tightening heated oxygen sensor 1
(front) with 22 mm hexagon nut
KV10114400
Heated oxygen sensor
wrench
NT636
Loosening or tightening heated oxygen sensor 2
(rear)
a: 22 mm
Commercial Service ToolsNJEC0008
Tool name Description
Fuel filler cap adapter
NT653
Checking fuel tank vacuum relief valve opening
pressure
Oxygen sensor thread
cleaner
NT778
Reconditioning the exhaust system threads before
installing a new oxygen sensor. Use with anti-
seize lubricant shown below.
a: 18 mm dia. with pitch 1.5 mm, for Zirconia
Oxygen Sensor
b: 12 mm dia. with pitch 1.25 mm, for Titania
Oxygen Sensor
Anti-seize lubricant (Per-
matex
TM133AR or
equivalent meeting MIL
specification MIL-A-907)
NT779
Lubricating oxygen sensor thread cleaning tool
when reconditioning exhaust system threads.
PREPARATIONQG
Special Service Tools
EC-20
Page 745 of 2898
Engine Control Component Parts LocationNJEC0009For more details of ECM location, refer to ªELECTRICAL UNIT LOCATIONº in EL section (EL-517).
NEF344A
ENGINE AND EMISSION CONTROL OVERALL SYSTEMQG
Engine Control Component Parts Location
EC-21
Page 746 of 2898
NEF325A
ENGINE AND EMISSION CONTROL OVERALL SYSTEMQG
Engine Control Component Parts Location (Cont'd)
EC-22
Page 747 of 2898
NEF326A
ENGINE AND EMISSION CONTROL OVERALL SYSTEMQG
Engine Control Component Parts Location (Cont'd)
EC-23
Page 748 of 2898
SEF599Y
ENGINE AND EMISSION CONTROL OVERALL SYSTEMQG
Engine Control Component Parts Location (Cont'd)
EC-24
Page 749 of 2898
Circuit DiagramNJEC0010SEDANNJEC0010S01Type-1NJEC0010S0101
HEC895
ENGINE AND EMISSION CONTROL OVERALL SYSTEMQG
Circuit Diagram
EC-25
Page 750 of 2898
Type-2NJEC0010S0102
HEC934
ENGINE AND EMISSION CONTROL OVERALL SYSTEMQG
Circuit Diagram (Cont'd)
EC-26