9 CHECK INTERMITTENT INCIDENT
1. Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-559.
©INSPECTION END
Main 12 Causes of OverheatingNJEC0667
Engine Step Inspection item Equipment Condition Reference page
OFF 1+Blocked radiator
+Blocked radiator grille
+Blocked bumper+Visual No blocking Ð
2+Coolant mixture+Coolant tester 50 - 50% coolant mixture See MA-20, ªRECOM-
MENDED FLUIDS AND
LUBRICANTSº.
3+Coolant level+Visual Coolant up to MAX level
in reservoir tank and
radiator filler neckSee LC-17, ªChanging
Engine Coolantº.
4+Radiator cap+Pressure tester 78 - 98 kPa
(0.78 - 0.98 bar, 0.8 - 1.0
kg/cm
2, 11 - 14 psi)See LC-37, ªSystem
Checkº.
ON*
25+Coolant leaks+Visual No leaks See LC-37, ªSystem
Checkº.
ON*
26+Thermostat+Touch the upper and
lower radiator hosesBoth hoses should be
hotSee LC-40, ªThermostatº
and ªRadiatorº.
ON*
17+Cooling fan+CONSULT-II Operating See Trouble Diagnosis
for DTC P1217, EC-618.
OFF 8+Combustion gas leak+Color checker chemi-
cal tester 4 Gas ana-
lyzerNegative Ð
ON*
39+Coolant temperature
gauge+Visual Gauge less than 3/4
when drivingÐ
+Coolant overflow to
reservoir tank+Visual No overflow during driv-
ing and idlingSee LC-43, ªChanging
Engine Coolantº.
OFF*
410+Coolant return from
reservoir tank to radia-
tor+Visual Should be initial level in
reservoir tankSee LC-43, ªREFILLING
ENGINE COOLANTº.
OFF 11+Cylinder head+Straight gauge feeler
gauge0.1mm (0.004 in) Maxi-
mum distortion (warping)See EM-121, ªInspec-
tionº.
12+Cylinder block and
pistons+Visual No scuffing on cylinder
walls or pistonSee EM-143, ªInspec-
tionº.
*1: Turn the ignition switch ON.
*2: Engine running at 3,000 rpm for 10 minutes.
*3: Drive at 90 km/h (55 MPH) for 30 minutes and then let idle for 10 minutes.
*4: After 60 minutes of cool down time.
For more information, refer to LC-46, ªOVERHEATING CAUSE ANALYSISº.
DTC P1217 OVER HEATYD
Diagnostic Procedure (Cont'd)
EC-633
SEF437Y
DescriptionNJEC0727SYSTEM DESCRIPTIONNJEC0727S01The ECM and the electronic control fuel injection pump control unit
(abbreviated as the injection pump control unit) perform the real
time communication (signal exchange).
The ECM transmits the signals of the target fuel injection amount,
target fuel injection timing, and engine speed, etc., and receives
the signals of the pump speed and fuel temperature, etc. from the
injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and timing
control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-into
electronic control fuel injection pump. These malfunction informa-
tion are transferred through the line (circuit) from injection pump
control unit to ECM.
FUEL INJECTION AMOUNT CONTROLNJEC0727S02In accordance with the target fuel injection amount signal from the
ECM, the injection amount is controlled by controlling the spill valve
in the injection pump and by changing the needle opening time.
FUEL INJECTION TIMING CONTROLNJEC0727S03Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring by
performing the duty control of the timing control valve in the injec-
tion pump and by adjusting the pressure of the timer piston high
pressure chamber.
FUEL TEMPERATURE SENSORNJEC0727S04The sensor detects the fuel temperature in the injection pump and
calibrates the injection amount change by the fuel temperature.
CAM RING POSITION SENSORNJEC0727S05The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic resis-
tance element sensor. The cam ring position sensor synchronizes
with the cam ring, and detects the actual advance amount. The
injection pump control unit measures the injection pump revolution
by the signal of the cam ring position sensor.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0728Remarks: Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
FUEL TEMP SEN+Engine: After warming up More than 40ÉC (104ÉF)
SPILL/V+Engine: After warming up, idle the engine. Approx. 12 - 13ÉCA
INT/A VOLUME+Engine: After warming up, idle the engine. Approx. 150 - 450 mg/st
F/CUT SIGNAL+Engine: After warming up Idle ON
DTC P1241 P7´F/INJ TIMG FBYD
Description
EC-634
SEF437Y
DescriptionNJEC0714SYSTEM DESCRIPTIONNJEC0714S01The ECM and the electronic control fuel injection pump control unit
(abbreviated as the injection pump control unit) perform the real
time communication (signal exchange).
The ECM transmits the signals of the target fuel injection amount,
target fuel injection timing, and engine speed, etc., and receives
the signals of the pump speed and fuel temperature, etc. from the
injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and timing
control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-into
electronic control fuel injection pump. These malfunction informa-
tion are transferred through the line (circuit) from injection pump
control unit to ECM.
FUEL INJECTION AMOUNT CONTROLNJEC0714S02In accordance with the target fuel injection amount signal from the
ECM, the injection amount is controlled by controlling the spill valve
in the injection pump and by changing the needle opening time.
FUEL INJECTION TIMING CONTROLNJEC0714S03Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring by
performing the duty control of the timing control valve in the injec-
tion pump and by adjusting the pressure of the timer piston high
pressure chamber.
FUEL TEMPERATURE SENSORNJEC0714S04The sensor detects the fuel temperature in the injection pump and
calibrates the injection amount change by the fuel temperature.
CAM RING POSITION SENSORNJEC0714S05The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic resis-
tance element sensor. The cam ring position sensor synchronizes
with the cam ring, and detects the actual advance amount. The
injection pump control unit measures the injection pump revolution
by the signal of the cam ring position sensor.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0715Remarks: Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
FUEL TEMP SEN+Engine: After warming up More than 40ÉC (104ÉF)
SPILL/V+Engine: After warming up, idle the engine. Approx. 12 - 13ÉCA
INT/A VOLUME+Engine: After warming up, idle the engine. Approx. 150 - 450 mg/st
F/CUT SIGNAL+Engine: After warming up Idle ON
DTC P1251 P4´SPILL/V CIRCYD
Description
EC-640
SEF437Y
DescriptionNJEC0700SYSTEM DESCRIPTIONNJEC0700S01The ECM and the electronic control fuel injection pump control unit
(abbreviated as the injection pump control unit) perform the real
time communication (signal exchange).
The ECM transmits the signals of the target fuel injection amount,
target fuel injection timing, and engine speed, etc., and receives
the signals of the pump speed and fuel temperature, etc. from the
injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and timing
control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-into
electronic control fuel injection pump. These malfunction informa-
tion are transferred through the line (circuit) from injection pump
control unit to ECM.
FUEL INJECTION AMOUNT CONTROLNJEC0700S02In accordance with the target fuel injection amount signal from the
ECM, the injection amount is controlled by controlling the spill valve
in the injection pump and by changing the needle opening time.
FUEL INJECTION TIMING CONTROLNJEC0700S03Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring by
performing the duty control of the timing control valve in the injec-
tion pump and by adjusting the pressure of the timer piston high
pressure chamber.
FUEL TEMPERATURE SENSORNJEC0700S04The sensor detects the fuel temperature in the injection pump and
calibrates the injection amount change by the fuel temperature.
CAM RING POSITION SENSORNJEC0700S05The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic resis-
tance element sensor. The cam ring position sensor synchronizes
with the cam ring, and detects the actual advance amount. The
injection pump control unit measures the injection pump revolution
by the signal of the cam ring position sensor.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0701Remarks: Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
FUEL TEMP SEN+Engine: After warming up More than 40ÉC (104ÉF)
SPILL/V+Engine: After warming up, idle the engine. Approx. 12 - 13ÉCA
INT/A VOLUME+Engine: After warming up, idle the engine. Approx. 150 - 450 mg/st
F/CUT SIGNAL+Engine: After warming up Idle ON
DTC P1337 P2´DTC PULSE SIGYD
Description
EC-646
SEF437Y
DescriptionNJEC0693SYSTEM DESCRIPTIONNJEC0693S01The ECM and the electronic control fuel injection pump control unit
(abbreviated as the injection pump control unit) perform the real
time communication (signal exchange).
The ECM transmits the signals of the target fuel injection amount,
target fuel injection timing, and engine speed, etc., and receives
the signals of the pump speed and fuel temperature, etc. from the
injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and timing
control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-into
electronic control fuel injection pump. These malfunction informa-
tion are transferred through the line (circuit) from injection pump
control unit to ECM.
FUEL INJECTION AMOUNT CONTROLNJEC0693S02In accordance with the target fuel injection amount signal from the
ECM, the injection amount is controlled by controlling the spill valve
in the injection pump and by changing the needle opening time.
FUEL INJECTION TIMING CONTROLNJEC0693S03Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring by
performing the duty control of the timing control valve in the injec-
tion pump and by adjusting the pressure of the timer piston high
pressure chamber.
FUEL TEMPERATURE SENSORNJEC0693S04The sensor detects the fuel temperature in the injection pump and
calibrates the injection amount change by the fuel temperature.
CAM RING POSITION SENSORNJEC0693S05The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic resis-
tance element sensor. The cam ring position sensor synchronizes
with the cam ring, and detects the actual advance amount. The
injection pump control unit measures the injection pump revolution
by the signal of the cam ring position sensor.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0694Remarks: Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
FUEL TEMP SEN+Engine: After warming up More than 40ÉC (104ÉF)
SPILL/V+Engine: After warming up, idle the engine. Approx. 12 - 13ÉCA
INT/A VOLUME+Engine: After warming up, idle the engine. Approx. 150 - 450 mg/st
F/CUT SIGNAL+Engine: After warming up Idle ON
DTC P1341 P1´CAM POS SENYD
Description
EC-652
SEF437Y
DescriptionNJEC0707SYSTEM DESCRIPTIONNJEC0707S01The ECM and the electronic control fuel injection pump control unit
(abbreviated as the injection pump control unit) perform the real
time communication (signal exchange).
The ECM transmits the signals of the target fuel injection amount,
target fuel injection timing, and engine speed, etc., and receives
the signals of the pump speed and fuel temperature, etc. from the
injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and timing
control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-into
electronic control fuel injection pump. These malfunction informa-
tion are transferred through the line (circuit) from injection pump
control unit to ECM.
FUEL INJECTION AMOUNT CONTROLNJEC0707S02In accordance with the target fuel injection amount signal from the
ECM, the injection amount is controlled by controlling the spill valve
in the injection pump and by changing the needle opening time.
FUEL INJECTION TIMING CONTROLNJEC0707S03Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring by
performing the duty control of the timing control valve in the injec-
tion pump and by adjusting the pressure of the timer piston high
pressure chamber.
FUEL TEMPERATURE SENSORNJEC0707S04The sensor detects the fuel temperature in the injection pump and
calibrates the injection amount change by the fuel temperature.
CAM RING POSITION SENSORNJEC0707S05The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic resis-
tance element sensor. The cam ring position sensor synchronizes
with the cam ring, and detects the actual advance amount. The
injection pump control unit measures the injection pump revolution
by the signal of the cam ring position sensor.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0708Remarks: Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
FUEL TEMP SEN+Engine: After warming up More than 40ÉC (104ÉF)
SPILL/V+Engine: After warming up Approx. 12 - 13ÉCA
INT/A VOLUME+Engine: After warming up, idle the engine. Approx. 150 - 450 mg/st
F/CUT SIGNAL+Engine: After warming up Idle ON
DTC P1600 P3´PUMP COMM LINEYD
Description
EC-658
SEF437Y
DescriptionNJEC0721SYSTEM DESCRIPTIONNJEC0721S01The ECM and the electronic control fuel injection pump control unit
(abbreviated as the injection pump control unit) perform the real
time communication (signal exchange).
The ECM transmits the signals of the target fuel injection amount,
target fuel injection timing, and engine speed, etc., and receives
the signals of the pump speed and fuel temperature, etc. from the
injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and timing
control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-into
electronic control fuel injection pump. These malfunction informa-
tion are transferred through the line (circuit) from injection pump
control unit to ECM.
FUEL INJECTION AMOUNT CONTROLNJEC0721S02In accordance with the target fuel injection amount signal from the
ECM, the injection amount is controlled by controlling the spill valve
in the injection pump and by changing the needle opening time.
FUEL INJECTION TIMING CONTROLNJEC0721S03Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring by
performing the duty control of the timing control valve in the injec-
tion pump and by adjusting the pressure of the timer piston high
pressure chamber.
FUEL TEMPERATURE SENSORNJEC0721S04The sensor detects the fuel temperature in the injection pump and
calibrates the injection amount change by the fuel temperature.
CAM RING POSITION SENSORNJEC0721S05The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic resis-
tance element sensor. The cam ring position sensor synchronizes
with the cam ring, and detects the actual advance amount. The
injection pump control unit measures the injection pump revolution
by the signal of the cam ring position sensor.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0722Remarks: Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
FUEL TEMP SEN+Engine: After warming up More than 40ÉC (104ÉF)
SPILL/V+Engine: After warming up, idle the engine. Approx. 12 - 13ÉCA
INT/A VOLUME+Engine: After warming up, idle the engine. Approx. 150 - 450 mg/st
F/CUT SIGNAL+Engine: After warming up Idle ON
DTC P1690 P5´PUMP C/MODULEYD
Description
EC-674
DescriptionNJEC0764SYSTEM DESCRIPTIONNJEC0764S01
Sensor Input Signal to ECM ECM Function Actuator
Electronic controlled fuel injection pump Fuel injection signal
EGR volume con-
trolEGR volume control
valve Crankshaft position sensor (TDC) Engine speed
Vehicle speed sensor Vehicle speed
Engine coolant temperature sensor Engine coolant temperature
Ignition switch Start signal
Accelerator position sensor Accelerator position
Mass air flow sensor Amount of intake air
Air conditioner switch Air conditioner operation
Electrical load Electrical load signal
This system controls flow rate of EGR led from exhaust manifold
to intake manifold. The opening of the EGR by-pass passage in the
EGR volume control valve changes to control the flow rate. A
built-in step motor moves the valve in steps corresponding to the
ECM output pulses. The opening of the valve varies for optimum
engine control. The optimum value stored in the ECM is determined
by considering various engine conditions.
The EGR volume control valve remains close under the following
conditions.
+Engine stopped
+Engine starting
+Low engine coolant temperature
+Excessively high engine coolant temperature
+High engine speed
+Wide open throttle
SEF908Y
SEF411Y
COMPONENT DESCRIPTIONNJEC0764S02EGR Volume Control ValveNJEC0764S0201The EGR volume control valve uses a step motor to control the flow
rate of EGR from exhaust manifold. This motor has four winding
phases. It operates according to the output pulse signal of the
ECM. Two windings are turned ON and OFF in sequence. Each
time an ON pulse is issued, the valve opens or closes, changing
the flow rate. When no change in the flow rate is needed, the ECM
does not issue the pulse signal. A certain voltage signal is issued
so that the valve remains at that particular opening.
EGR VOLUME CONTROL SYSTEMYD
Description
EC-686