Diagnostic ProcedureNCEC0195
1 CHECK FOR EXHAUST AIR LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust air leak before the three way catalyst.
SEF099P
OK or NG
OK©GO TO 2.
NG©Repair or replace.
2 CHECK HEATED OXYGEN SENSOR 1 (FRONT) CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect heated oxygen sensor 1 (front) harness connector and ECM harness connector.
SEF207X3. Check harness continuity between ECM terminal 62 and heated oxygen sensor 1 (front) harness connector terminal 2.
Refer to wiring diagram.
Continuity should exist.
4. Check harness continuity between ECM terminal 62 (or terminal 2) and ground.
Continuity should not exist.
5. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 3.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
3 CHECK FUEL PRESSURE
1. Release fuel pressure to zero.
Refer to EC-SR-31.
2. Install fuel pressure gauge and check fuel pressure.
At idling:
When fuel pressure regulator valve vacuum hose is connected.
Approximately 235 kPa (2.35 bar, 2.4 kg/cm
2, 34 psi)
When fuel pressure regulator valve vacuum hose is disconnected.
Approximately 294 kPa (2.94 bar, 3.0 kg/cm
2, 43 psi)
OK or NG
OK©GO TO 5.
NG©GO TO 4.
Heated oxygen sensor 1
(front) harness connector
Heated oxygen
sensor 1 (front)
DTC P0172 FUEL INJECTION SYSTEM FUNCTION
(RICH SIDE)SR20DE
Diagnostic Procedure
EC-221
4 DETECT MALFUNCTIONING PART
Check the following.
IFuel pump and circuit (Refer to EC-SR-316.)
IFuel pressure regulator (Refer to EC-SR-32.)
©Repair or replace.
5 CHECK MASS AIR FLOW SENSOR
With CONSULT-II
Check ªMASS AIR FLOWº in ªDATA MONITORº mode with CONSULT-II.
at idling: 2.5 - 5.0 g×m/sec
at 2,500 rpm: 7.1 - 12.5 g×m/sec
With GST
Check mass air flow sensor signal in MODE 1 with GST.
at idling: 2.5 - 5.0 g×m/sec
at 2,500 rpm: 7.1 - 12.5 g×m/sec
OK or NG
OK©GO TO 6.
NG©Check connectors for rusted terminals or loose connections in the mass air flow sensor
circuit or engine grounds. Refer to EC-SR-123.
6 CHECK FUNCTION OF INJECTORS
With CONSULT-II
1. Install all parts removed.
2. Start engine.
3. Perform ªPOWER BALANCEº in ªACTIVE TESTº mode with CONSULT-II.
NEF105A4. Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-II
1. Install all parts removed.
2. Start engine.
3. Listen to each injector operating sound.
MEC703BClicking noise should be heard.
OK or NG
OK©GO TO 7.
NG©Perform trouble diagnosis for ªINJECTORSº, EC-SR-304.
DTC P0172 FUEL INJECTION SYSTEM FUNCTION
(RICH SIDE)SR20DE
Diagnostic Procedure (Cont'd)
EC-222
On Board Diagnosis LogicNCEC0202If a misfire occurs, the engine speed will fluctuate. If the fluctuation is detected by the crankshaft position sen-
sor (OBD), the misfire is diagnosed.
Sensor Input Signal to ECM ECM function
Crankshaft position sensor (OBD) Engine speed On board diagnosis of misfire
The misfire detection logic consists of the following two conditions.
1. One Trip Detection Logic (Three Way Catalyst Damage)
On the first trip that a misfire condition occurs that can damage the three way catalyst (TWC) due to
overheating, the MI will blink.
When a misfire condition occurs, the ECM monitors the CKP sensor signal every 200 engine revolutions
for a change.
When the misfire condition decreases to a level that will not damage the TWC, the MI will turn off.
If another misfire condition occurs that can damage the TWC on a second trip, the MI will blink.
When the misfire condition decreases to a level that will not damage the TWC, the MI will remain on.
If another misfire condition occurs that can damage the TWC, the MI will begin to blink again.
2. Two Trip Detection Logic (Exhaust quality deterioration)
For misfire conditions that will not damage the TWC (but will affect exhaust vehicle emissions), the MI will
only light when the misfire is detected on a second trip. During this condition, the ECM monitors the CKP
sensor signal every 1,000 engine revolutions.
A misfire malfunction can be detected on any one cylinder or on multiple cylinders.
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0300
0300IMultiple cylinders misfire.IImproper spark plug
IInsufficient compression
IIncorrect fuel pressure
IThe injector circuit is open or shorted
IInjectors
IIntake air leak
IThe ignition secondary circuit is open or
shorted
ILack of fuel
IHeated oxygen sensor 1 (front)
IDrive plate/Flywheel
IIncorrect distributor rotor P0301
0301INo. 1 cylinder misfires.
P0302
0302INo. 2 cylinder misfires.
P0303
0303INo. 3 cylinder misfires.
P0304
0304INo. 4 cylinder misfires.
DTC Confirmation ProcedureNCEC0203CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
TESTING CONDITION:
IAlways perform at a temperature above þ10ÉC (14ÉF).
With CONSULT-II
1) Turn ignition switch ªONº, and select ªDATA MONITORº mode
with CONSULT-II.
2) Start engine and warm it up to normal operating temperature.
3) Turn ignition switch ªOFFº and wait at least 9 seconds.
4) Start engine again and drive at 1,500 - 3,000 rpm for at least
3 minutes.
Hold the accelerator pedal as steady as possible.
NOTE:
Refer to the freeze frame data for the test driving conditions.
5) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-SR-225.
With GST
Follow the procedure ªWith CONSULT-IIº above.
NEF068A
DTC P0300 - P0304 NO.4-1CYLINDER MISFIRE,
MULTIPLE CYLINDER MISFIRESR20DE
On Board Diagnosis Logic
EC-224
7 CHECK SPARK PLUGS
Remove the spark plugs and check for fouling, etc.
SEF156I
OK or NG
OK©GO TO 9.
NG©Repair or replace spark plug(s) with standard type one(s). For spark plug type, refer to
ªENGINE MAINTENANCEº in MA section.
8 CHECK COMPRESSION PRESSURE
Refer to EM section.
ICheck compression pressure.
Standard:
1,226 kPa (12.26 bar, 12.5 kg/cm
2, 178 psi)/300 rpm
Minimum:
1,030 kPa (10.30 bar, 10.5 kg/cm
2, 149 psi)/300 rpm
Difference between each cylinder:
98 kPa (0.98 bar, 1.0 kg/cm
2, 14 psi)/300 rpm
OK or NG
OK©GO TO 10.
NG©Check pistons, piston rings, valves, valve seats and cylinder head gaskets.
9 CHECK FUEL PRESSURE
1. Install any parts removed.
2. Release fuel pressure to zero. Refer to EC-SR-31.
3. Install fuel pressure gauge and check fuel pressure.
SEF194XAt idle:
Approx. 235 kPa (2.35 bar, 2.4 kg/cm2, 34 psi)
OK or NG
OK©GO TO 12.
NG©GO TO 11.
Fuel filter
DTC P0300 - P0304 NO.4-1CYLINDER MISFIRE,
MULTIPLE CYLINDER MISFIRESR20DE
Diagnostic Procedure (Cont'd)
EC-227
10 DETECT MALFUNCTIONING PART
Check the following.
IFuel pump and circuit Refer to EC-SR-320.
IFuel pressure regulator Refer to EC-SR-32.
IFuel lines Refer to ªENGINE MAINTENANCEº in MA section.
IFuel filter for clogging
©Repair or replace.
11 CHECK IGNITION TIMING
Perform ªBasic Inspectionº, EC-SR-84.
OK or NG
OK©GO TO 13.
NG©Adjust ignition timing.
12 CHECK HEATED OXYGEN SENSOR 1 (FRONT)
Refer to ªComponent Inspectionº, EC-SR-154.
OK or NG
OK©GO TO 14.
NG©Replace heated oxygen sensor 1 (front).
13 CHECK MASS AIR FLOW SENSOR
With CONSULT-II
Check ªMASS AIR FLOWº in ªDATA MONITORº mode with CONSULT-II.
at idling: 2.5 - 5.0 g×m/sec
at 2,500 rpm: 7.1 - 12.5 g×m/sec
With GST
Check mass air flow sensor signal in MODE 1 with GST.
at idling: 2.5 - 5.0 g×m/sec
at 2,500 rpm: 7.1 - 12.5 g×m/sec
OK or NG
OK©GO TO 16.
NG©GO TO 15.
14 CHECK CONNECTORS
Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or engine grounds.
Refer to EC-SR-120.
OK or NG
NG©Repair or replace it.
15 CHECK SYMPTOM MATRIX CHART
Check items on the rough idle symptom in ªSymptom Matrix Chartº, EC-SR-94.
OK or NG
OK©GO TO 17.
NG©Repair or replace.
DTC P0300 - P0304 NO.4-1CYLINDER MISFIRE,
MULTIPLE CYLINDER MISFIRESR20DE
Diagnostic Procedure (Cont'd)
EC-228
Diagnostic ProcedureNCEC0448
1 CHECK OVERALL FUNCTION
1. Turn ignition switch ªONº.
2. Pinch fuel feed hose with fingers.
SEF241XFuel pressure pulsation should be felt on the fuel feed hose for 1 second after ignition switch is turned ªONº.
OK or NG
OK©INSPECTION END
NG©GO TO 2.
2 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect fuel pump relay located on the fuse block.
SEF071X3. Turn ignition switch ªONº.
4. Check voltage between terminals 1, 3 and ground with CONSULT-II or tester.
SEF144XVoltage: Battery voltage
OK or NG
OK©GO TO 4.
NG©GO TO 3.
Fuel filter
Pinch
FUEL PUMPSR20DE
Diagnostic Procedure
EC-318
Fuel Pressure RegulatorNCEC0467
Fuel pressure at idling
kPa (bar, kg/cm2, psi)Vacuum hose is connected Approximately 235 (2.35, 2.4, 34)
Vacuum hose is disconnected Approximately 294 (2.94, 3.0, 43)
Idle Speed and Ignition TimingNCEC0468
Target idle speed*1 rpm No-load*3 (in ªPº or ªNº position) 750 50
Air conditioner: ON rpm In ªPº or ªNº position 825 or more
Ignition timing*2 In ªPº or ªNº position 15É 2É BTDC
Throttle position sensor idle position V0.35 - 0.65
*1: Throttle position sensor harness connector connected
*2: Throttle position sensor harness connector disconnected
*3: Under the following conditions:
IAir conditioner switch: OFF
IElectrical load: OFF (Lights, heater fan & rear window defogger)
ISteering wheel: Kept in straight-ahead position
Ignition CoilNCEC0574
Primary voltage VBattery voltage (11 - 14)
Primary resistance [at 25ÉC (77ÉF)] kW2.2
Secondary resistance [at 25ÉC (77ÉF)] kWApproximately 17
Mass Air Flow SensorNCEC0470
Supply voltage (Heater) VBattery voltage (11 - 14)
Supply voltage (Sensor) VApproximately 5
Output voltage V1.3 - 1.7*
Mass air flow
(Using CONSULT-II or GST) g×m/sec2.5 - 5.0 at idle*
7.1 - 12.5 at 2,500 rpm*
*: Engine is warmed up to normal operating temperature and idling under no-load.
Engine Coolant Temperature SensorNCEC0471
Temperature ÉC (ÉF) Resistance kW
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
Fuel PumpNCEC0473
Resistance [at 25ÉC (77ÉF)]W0.2 - 5.0
IACV-AAC ValveNCEC0474
Resistance [at 20ÉC (68ÉF)]W
Between terminals1-2,2-3,4-5and5-620-24
InjectorNCEC0475
Resistance [at 25ÉC (77ÉF)]W13.5 - 17.5
SERVICE DATA AND SPECIFICATIONS (SDS)
Fuel Pressure Regulator
EC-330
Bulb Replacement
The headlamp is a semi-sealed beam type which uses a replace-
able halogen bulb. The bulb can be replaced from the engine
compartment side without removing the headlamp body.
Grasp only the plastic base when handling the bulb.
Never touch the glass envelope.
1. Disconnect the battery cable.
2. Turn the bulb retaining ring counterclockwise until it is free
from the headlamp reflector, and then remove it.
3. Disconnect the harness connector from the back side of the
bulb.
4. Remove the headlamp bulb carefully. Do not shake or rotate
the bulb when removing it.
5. Install in the reverse order of removal.
CAUTION:
Do not leave headlamp reflector without bulb for a long
period of time. Dust, moisture, smoke, etc. entering head-
lamp body may affect the performance of the headlamp.
Remove headlamp bulb from the headlamp reflector just
before a replacement bulb is installed.
Aiming Adjustment
When performing headlamp aiming adjustment, use an aiming
machine, aiming wall screen or headlamp tester. Aimers should
be in good repair, calibrated and operated in accordance with
respective operation manuals.
If any aimer is not available, aiming adjustment can be done as
follows:
For details, refer to the regulations in your own country.
a. Keep all tires inflated to correct pressures.
b. Place vehicle and tester on one and same flat surface.
c. See that there is no-load in vehicle (coolant, engine oil
filled up to correct level and full fuel tank) other than the
driver (or equivalent weight placed in driver’s position).
CAUTION:
Be sure aiming switch is set to“0”when performing aiming
adjustment on vehicles equipped with headlamp aiming
control.
SEL995K Rubber
capOpenBulb cover
Lock
Push
to
remove
SEL466V
HEADLAMP (without Daytime Light System)—Conventional Type—
EL-70