Downloaded from www.Manualslib.com manuals search engine ENGINE GENERAL INFORMATION AND DIAGNOSIS 6-69
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Check vehicle and environmental condition for :
–Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Ambient temp. : –10 °C, 14 °F or higher
–Intake air temp. : 70 °C, 158 °F or lower
4) Start engine and drive vehicle under usual driving condition (described in DTC confirmation procedure of
DTC P0136) for 5 min. or longer and until engine is warmed up to normal operating temperature.
5) Keep vehicle speed at 30 – 40 mph, 50 – 60 km/h in 5th gear or “D” range for 5 min. or more.
6) Stop vehicle (do not turn ignition switch OFF).
7) Check pending DTC in “ON BOARD TEST” or “PENDING DTC” mode and DTC in “DTC” mode.
INSPECTION
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester on a level road.
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag.
Flow Table”.
2 Is there DTC(s) other than fuel system
(DTC P0171 / P0172)?Go to applicable DTC
Diag. Flow Table.Go to Step 3.
3 Check HO2S-1 Output Voltage.
1) Connect scan tool to DLC with ignition switch
OFF. See Fig. 1.
2) Warm up engine to normal operating tempera-
ture and keep it at 2000 r/min. for 60 sec.
3) Repeat racing engine (Repeat depressing
accelerator pedal 5 to 6 times continuously and
take foot off from pedal to enrich and enlean
A/F mixture).
Does HO2S-1 output voltage deflect between
below 0.3 V and over 0.6 V repeatedly?Go to Step 4. Go to DTC P0130 Diag.
Flow Table (HO2S-1 cir-
cuit check).
4 Check Fuel Pressure (Refer to Section 6E for
details).
1) Release fuel pressure from fuel feed line.
2) Install fuel pressure gauge. See Fig. 2.
3) Check fuel pressure.
Fuel pressure specification
With fuel pump operating and engine at stop :
270 – 310 kPa, 2.7 – 3.1 kg/cm
2, 38.4 – 44.0 psi.
At specified idle speed :
210 – 260 kPa, 2.1 – 2.6 kg/cm
2, 29.8 – 37.0 psi.
Is measured value as specified?Go to Step 5. Go to Diag. Flow Table
B-3 Fuel Pressure
Check.
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5 Check Fuel Injectors and Circuit.
1) Using sound scope (4) or such, check operating
sound of each injector (5) when engine is run-
ning. Cycle of operating sound should vary
according to engine speed. See Fig. 3.
If no sound or an unusual sound is heard, check
injector circuit (wire or coupler) or injector.
2) Turn ignition switch OFF and disconnect a fuel
injector connector.
3) Check for proper connection to fuel injector at
each terminal.
4) If OK, then check injector resistance.
See Fig. 4.
Injector resistance
11.3 – 13.8 ohm at 20 °C (68 °F)
5) Carry out steps 1) and 3) on each injector.
6) Check each injector for injected fuel volume
referring to Section 6E. See Fig. 5.
Injected fuel volume
43 – 47 cc/15 sec (1.45/1.51 – 1.58/1.65 US/
Imp.oz/15 sec)
7) Check each injector for fuel leakage after injec-
tor closed.
Fuel leakage
Less than 1 drop / min. (1)
Is check result in step 1) and 3) to 7) satisfactory?Go to Step 6. Check injector circuit or
replace fuel injector(s).
6 Check EVAP Canister Purge Valve.
1) Disconnect purge hose (2) from EVAP canister.
2) Place finger against the end of disconnected
hose.
3) Check that vacuum is not felt there when
engine is cool and running at idle. See Fig. 6.
Is vacuum felt?Check EVAP control
system (See Section
6E).Go to Step 7.
7 Check intake manifold absolute pressure sensor for
performance (See step 4) of DTC P0105 (No.11)
Diag. Flow Table).
Is it in good condition?Go to Step 8. Repair or replace.
8 Check engine coolant temp. sensor for perfor-
mance (See Section 6E).
Is it in good condition?Go to Step 9. Replace engine coolant
temp. sensor.
9 Check intake air temp. sensor for performance
(See Section 6E).
Is it in good condition?Go to Step 10. Replace intake air temp.
sensor.
10 Check throttle position sensor for performance
(See step 5) of DTC P0121 Diag. Flow Table).
Is it in good condition?Go to Step 11. Replace throttle position
sensor.
11 Check PCV valve for valve clogging
(See Section 6E).
Is it good condition?Substitute a known-
good ECM and recheck.Replace PCV valve. Step Action Yes No
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DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Check vehicle and environmental condition for :
–Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Ambient temp. : –10 °C, 14 °F or higher
–Intake air temp. : 70 °C, 158 °F or lower
–Engine coolant temp. : – 10 – 110 °C, 14 – 230 °F
4) Start engine and keep it at idle for 2 min. or more.
5) Check DTC in “DTC” mode and pending DTC in “ON BOARD TEST” or “PENDING DTC” mode.
6) If DTC is not detected at idle, consult usual driving based on information obtained in “Customer complaint
analysis” and “Freeze frame data check”.
INSPECTION
DTC DETECTING CONDITION POSSIBLE CAUSE
Engine under other than high revolution condition
Not on rough road
Engine speed changing rate (below specified value)
Manifold absolute pressure changing rate (below
specified value)
Throttle opening changing rate (below specified
value)
Misfire rate per 200 or 1000 engine revolutions (how
much and how often crankshaft revolution speed
changes) is higher than specified valueEngine overheating
Vacuum leaks (air inhaling) from air intake system
Ignition system malfunction (spark plug(s), high-
tension cord(s), ignition coil assembly)
Fuel pressure out of specification
Fuel injector malfunction (clogged or leakage)
Engine compression out of specification
Valve lash (clearance) out of specification
Manifold absolute pressure sensor malfunction
Engine coolant temp. sensor malfunction
PCV valve malfunction
EVAP control system malfunction
EGR system malfunction
NOTE:
Among different types of random misfire, if misfire occurs at cylinders 1 and 4 or cylinders 3 and 2
simultaneously, it may not possible to reconfirm DTC by using the following DTC confirmation proce-
dure. When diagnosing the trouble of DTC P0300 (Random misfire detected) of the engine which is
apparently misfiring, even if DTC P0300 cannot be reconfirmed by using the following DTC confirma-
tion procedure, proceed to the following Diag. Flow Table.
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester.
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine
Diag. Flow Table”.
2 Is there DTC other than Fuel system (DTC P0171/
P0172) and misfire (DTC P0300 – P0304)?Go to applicable DTC
Diag. Flow Table.Go to Step 3.
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3 Check Ignition System.
1) Remove spark plugs and check them for;
Air gap : 1.0 – 1.1 mm (0.040 – 0.043 in.) See Fig. 1.
Carbon deposits / Insulator damage / Plug type
If abnormality is found, adjust, clean or replace by
referring to Section 6F. (See CAUTION)
2) Disconnect all injector connectors. See Fig. 2.
3) Connect spark plugs to high tension cords and then
ground spark plugs.
4) Crank engine and check that each spark plug sparks.
Are above check results satisfactory?Go to Step 4. Check ignition sys-
tem parts (Refer to
Section 6F).
4 Check Fuel Pressure (Refer to Section 6E for details).
1) Release fuel pressure from fuel feed line.
2) Install fuel pressure gauge. See Fig. 3.
3) Check fuel pressure.
Fuel pressure specification
With fuel pump operating and engine at stop :
270 – 310 kPa, 2.7 – 3.1 kg/cm
2, 38.4 – 44.0 psi.
At specified idle speed :
210 – 260 kPa, 2.1 – 2.6 kg/cm
2, 29.8 – 37.0 psi.
Is measured value as specified?Go to Step 5. Go to Diag. Flow
Table B-3 fuel pres-
sure check.
5 Check Fuel Injectors and Circuit.
1) sing sound scope (1) or such, check operating sound
of each injector (2) when engine is running. Cycle of
operating sound should very according to engine
speed. See Fig 4.
If no sound or an unusual sound is heard, check
injector circuit (wire or coupler) or injector.
2) Turn ignition switch OFF and disconnect a fuel injec-
tor connector.
3) Check for proper connection to fuel injector at each
terminal.
4) If OK, then check injector resistance. See Fig. 5.
Injector resistance
11.3 – 13.8 ohm at 20 °C (68 °F)
5) Carry out steps 1) and 3) on each injector.
6) Check each injector for injected fuel volume referring
to Section 6E. See Fig. 6.
Injected fuel volume
43 – 47 cc/15 sec (1.45/1.51 – 1.58/1.65 US/Imp. oz/
15 sec)
7) Check each injector for fuel leakage after injector
closed.
Fuel leakage
Less than 1 drop/min.
Is check result in step 1) and 3) to 7) satisfactory?Go to Step 6. Check injector cir-
cuit or replace fuel
injector(s).
6 Check PCV valve for clogging (See Section 6E).
Is it in good condition?Go to Step 7. Replace PCV
valve. Step Action Yes No
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DTC P0325 (DTC No.17) Knock Sensor Circuit Malfunction
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Clear DTC, start engine and keep it at idle for 1 min.
2) Select “DTC” mode on scan tool and check DTC.
INSPECTION
DTC DETECTING CONDITION POSSIBLE CAUSE
Knock sensor voltage is 3.91 V or more
Knock sensor voltage is 1.23 V or less“W” circuit open or shorted to ground
Knock sensor malfunction
ECM malfunction
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag. Flow
Table”.
2 1) With engine running, check voltage from
“E19-25” terminal of ECM connector to
body ground. See Fig. 1.
2) Is voltage about 1.25 – 3.75 V?Knock sensor and its cir-
cuit are in good condition.
Intermittent trouble or
faulty ECM.
Recheck, referring to
“Intermittent Trouble” in
Section 0A.Go to Step 3.
3 1) Stop engine.
2) With ignition switch at OFF position, discon-
nect knock sensor connector.
3) With ignition switch at ON position, check
voltage from “W” to body ground terminal of
knock sensor connector. See Fig. 2.
Is it 4 – 5 V?Faulty knock sensor.
Substitute a known-good
knock sensor and
recheck.“W” wire open, shorted to
ground circuit or poor
“E19-25” connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.
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INSPECTION
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag.
Flow Table”.
2 Check CKP Sensor and connector for proper
installation.
Is CKP sensor installed properly and connector
connected securely?Go to Step 3. Correct.
3 Check Wire Harness and Connection.
1) Disconnect connector from CKP sensor.
2) Check for proper connection to CKP sensor at
each terminal.
3) If OK, turn ignition switch ON and check for
voltage at each terminal of sensor connector
disconnected. See Fig. 1.
Terminal “B+” : 10 – 14 V
Terminal “Vout” : 4 – 5 V
Terminal “GND” : 0 V
Is check result satisfactory?Go to Step 5. Go to Step 4.
4 Was terminal “Vout” voltage out of specification in
Step 3 check?“G/R” wire open, short or
poor connection.
If wire and connection are
OK, substitute a known-
good ECM and recheck.“Bl/B” or “B/R” wire
open, short or poor
connection.
5 Check Ground Circuit for Open.
1) Turn ignition switch OFF.
2) Check for continuity between “GND” terminal
of CKP sensor connector and engine ground.
Is continuity indicated?Go to Step 6.“B/R” wire open or
poor ground connec-
tion.
6 Check CKP Sensor for Operation.
1) Remove CKP sensor from sensor case.
2) Remove metal particles on end face of CKP
sensor, if any.
3) Connect each connector to ECM and CKP
sensor.
4) Turn ignition switch ON.
5) Check for voltage at terminal E19-23 of con-
nector connected to ECM by passing magnetic
substance (iron) (1) while keeping approxi-
mately 1 mm (0.03 in.) gap with respect to end
face of CKP sensor. See Fig. 2 and 3.
Does voltage vary from low (0 – 1 V) to high (4 – 5
V) or from high to low?Go to Step 7. Replace CKP sensor.
7 Check signal rotor for the following. See Fig. 4.
Damage
No foreign material attached
Is it in good condition?Intermittent trouble or
faulty ECM.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.Clean rotor teeth or
replace CKP sensor.
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INSPECTION
Step Action Yes No
1Was “Engine Diag. Flow Table” performed? Go to Step 2. Go to “Engine Diag.
Flow Table”.
2 Check CMP Sensor and connector for proper installa-
tion.
Is CMP sensor installed properly and connector con-
nected securely?Go to Step 3. Correct.
3 Check Wire Harness and Connection.
1) Disconnect connector from CMP sensor.
2) Check for proper connection to CMP sensor at
each terminal.
3) If OK, turn ignition switch ON and check for volt-
age at each terminal of sensor connector discon-
nected. See Fig. 1.
Terminal “B+” : 10 – 14 V
Terminal “Vout” : 4 – 5 V
Terminal “GND” : 0 V
Is check result satisfactory?Go to Step 5. Go to Step 4.
4 Was terminal “Vout” voltage out of specification in
Step 3 check?“W” wire open, short or
poor connection.
If wire and connection
are OK, substitute a
known-good ECM and
recheck.“Bl/B” or “B/R” wire
open, short or poor
connection.
5 Check Ground Circuit for Open.
1) Turn ignition switch OFF.
2) Check for continuity between “GND” terminal of
CMP sensor connector and engine ground.
Is continuity indicated?Go to Step 6.“B/R” wire open or
poor ground connec-
tion.
6 Check CMP Sensor for Operation.
1) Remove CMP sensor from sensor case.
2) Remove metal particles on end face of CMP sen-
sor, if any.
3) Connect each connector to ECM and CMP sensor.
4) Turn ignition switch ON.
5) Check for voltage at terminal E19-11 of connector
connected to ECM by passing magnetic sub-
stance (iron) (1) while keeping approximately 1
mm (0.03 in.) gap with respect to end face of CMP
sensor. See Fig. 2 and 3.
Does voltage vary from low (0 – 1 V) to high (4 – 5 V)
or from high to low?Go to Step 7. Replace CMP sen-
sor.
7 Check signal rotor for the following.
See Fig. 4.
Damage
No foreign material attached
Is it in good condition?Intermittent trouble or
faulty ECM.
Check for intermittent
referring to “Intermittent
and Poor Connection” in
Section 0A.Clean rotor teeth or
replace CMP sensor.
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DTC P0400 Exhaust Gas Recirculation Flow Malfunction
CIRCUIT DESCRIPTION
DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
Clear DTC with ignition switch ON, check vehicle and environmental condition for :
–Altitude (barometric pressure) : 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
–Ambient temp. : –10 °C, 14 °F or higher
–Intake air temp. : 70 °C, 122 °F or lower
1. EGR valve
DTC DETECTING CONDITION POSSIBLE CAUSE
While running at specified vehicle speed after engine warm-up
During deceleration (engine speed high with closed throttle position
ON) in which fuel cut is involved, difference in intake manifold absolute
pressure between when EGR valve is opened at specified value and
when it is closed is larger or smaller than specified value.
✱
✱✱ ✱2 driving cycle detection logic, monitoring once / 1 drivingEGR valve or its circuit
EGR passage
ECM
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and be very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 persons, a driver and a tester, on a level road.