Nissan Frontier. Manual - part 424

P0420 THREE WAY CATALYST FUNCTION

EC-267

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

Overall Function Check

INFOID:0000000009480928

Use this procedure to check the overall function of the three way catalyst (Manifold). During this check, a 1st

trip DTC might not be confirmed.

 With GST

1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Open engine hood.
6. Set voltmeter probe between ECM terminal 33 (HO2S2 signal) and ground.
7. Keep engine speed at 2,500 rpm constant under no load.
8. Make sure that the voltage does not vary for more than 5 seconds.

If the voltage fluctuation cycle takes less than 5 seconds, go to 

EC-267, "Diagnosis Procedure"

.

• 1 cycle: 0.6 - 1.0 V 

→ 0 - 0.3 V → 0.6 - 1.0 V

Diagnosis Procedure

INFOID:0000000009480929

1.

CHECK EXHAUST SYSTEM

Visually check exhaust tubes and muffler for dents.
OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace.

2.

CHECK EXHAUST GAS LEAK

1. Start engine and run it at idle.

2. Listen for an exhaust gas leak before the three way catalyst (manifold).

OK or NG

OK

>> GO TO 3.

NG

>> Repair or replace.

3.

CHECK INTAKE AIR LEAK

Listen for an intake air leak after the mass air flow sensor.
OK or NG

OK

>> GO TO 4.

NG

>> Repair or replace.

4.

CHECK IGNITION TIMING

Check the following items. Refer to 

EC-117, "Basic Inspection"

.

PBIB1216E

EC-268

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

P0420 THREE WAY CATALYST FUNCTION

OK or NG

OK

>> GO TO 5.

NG

>> Follow the 

EC-117, "Basic Inspection"

.

5.

CHECK FUEL INJECTOR

1. Stop engine and then turn ignition switch ON.

2. Check voltage between ECM terminals 29, 30, 31, 32 and ground with CONSULT or tester.

OK or NG

OK

>> GO TO 6.

NG

>> Perform 

EC-439, "Diagnosis Procedure"

.

6.

CHECK FUNCTION OF IGNITION COIL-I

CAUTION:

Do the following procedure in the place where ventilation is good without the combustible.

1. Turn ignition switch OFF.

2. Remove fuel pump fuse in IPDM E/R to release fuel pressure.

NOTE:

Do not use CONSULT to release fuel pressure, or fuel pressure

applies again during the following procedure.

3. Start engine.

4. After engine stalls, crank it two or three times to release all fuel

pressure.

5. Turn ignition switch OFF.

6. Remove all ignition coil harness connectors to avoid the electri-

cal discharge from the ignition coils.

7. Remove ignition coil and spark plug of the cylinder to be

checked.

8. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.

9. Connect spark plug and harness connector to ignition coil.

10. Fix ignition coil using a rope etc. with gap of 13 - 17 mm

between the edge of the spark plug and grounded metal portion

as shown in the figure.

11. Crank engine for about three seconds, and check whether spark

is generated between the spark plug and the grounded metal

portion.

CAUTION:

• Never approach to the spark plug and the ignition coil

within 50cm. Be careful not to get an electrical shock

while checking, because the electrical discharge voltage

becomes 20kV or more.

• It might cause to damage the ignition coil if the gap of more than 17 mm is taken.

NOTE:

When the gap is less than 13 mm, the spark might be generated even if the coil is malfunctioning.

OK or NG

OK

>> GO TO 10.

NG

>> GO TO 7.

7.

CHECK FUNCTION OF IGNITION COIL-II

Items

Specifications

Target idle speed

A/T: 700 

± 50 rpm (in P or N position)

M/T: 625 

± 50 rpm (in Neutral position)

Ignition timing

A/T: 15 

± 5° BTDC (in P or N position)

M/T: 15 

± 5° BTDC (in Neutral position)

Voltage: Battery voltage

Spark should be generated.

BBIA0534E

PBIB2325E

P0420 THREE WAY CATALYST FUNCTION

EC-269

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

1. Turn ignition switch OFF.

2. Disconnect spark plug and connect a known-good spark plug.

3. Crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and

the grounded metal portion.

OK or NG

OK

>> GO TO 8.

NG

>> Check ignition coil, power transistor and their circuits. Refer to 

EC-446

.

8.

CHECK SPARK PLUG

Check the initial spark plug for fouling, etc. Refer to 

EM-36,

"Removal and Installation"

.

OK or NG

OK

>> Replace spark plug(s) with standard type one(s).

NG

>> 1. Repair or clean spark plug.

2. GO TO 9.

9.

CHECK FUNCTION OF IGNITION COIL-III

1. Reconnect the initial spark plugs.

2. Crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and

the grounded portion.

OK or NG

OK

>> INSPECTION END

NG

>> Replace spark plug(s) with standard type one(s). For spark plug type. Refer to 

EM-36, "Removal

and Installation"

.

10.

CHECK FUEL INJECTOR

1. Turn ignition switch OFF.

2. Remove fuel injector assembly. Refer to 

EM-39, "Removal and Installation"

.

Keep fuel hose and all fuel injectors connected to fuel injector gallery.

3. Reconnect all fuel injector harness connectors.

4. Disconnect all ignition coil harness connectors.

5. Turn ignition switch ON.

check that fuel does not drip from fuel injector.

OK or NG

OK (Does not drip)>>GO TO 11.

NG (Drips)>>Replace the fuel injector(s) from which fuel is dripping. Refer to 

EM-39, "Removal and Installa-

tion"

.

11.

CHECK INTERMITTENT INCIDENT

Perform

GI-42, "Intermittent Incident"

.

Trouble is fixed>>INSPECTION END

Trouble is not fixed>>Replace three way catalyst (manifold). Refer to 

EM-31, "Exploded View"

.

Spark should be generated.

SEF156I

Spark should be generated.

EC-270

< DTC/CIRCUIT DIAGNOSIS >

[QR25DE]

P0441 EVAP CONTROL SYSTEM

P0441 EVAP CONTROL SYSTEM

System Description

INFOID:0000000009480930

NOTE:

If DTC P0441 is displayed with other DTC such as P2122, P2123 P2127, P2128, P2138, first perform

trouble diagnosis for other DTC.

In this evaporative emission (EVAP) control system, purge flow occurs during non-closed throttle conditions.

Purge volume is related to air intake volume. Under normal purge conditions (non-closed throttle), the EVAP

canister purge volume control solenoid valve is open to admit purge flow. Purge flow exposes the EVAP con-

trol system pressure sensor to intake manifold vacuum.

On Board Diagnosis Logic

INFOID:0000000009480931

Under normal conditions (non-closed throttle), sensor output voltage indicates if pressure drop and purge flow

are adequate. If not, a malfunction is determined.

DTC Confirmation Procedure

INFOID:0000000009480932

CAUTION:

Always drive vehicle at a safe speed.

NOTE:

If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at

least 10 seconds before conducting the next test.

TESTING CONDITION:

Always perform test at a temperature of 5

°C (41°F) or more.

 WITH CONSULT

1. Start engine and warm it up to normal operating temperature.

PBIB3640E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0441
0441

EVAP control system in-
correct purge flow

EVAP control system does not operate properly, 
EVAP control system has a leak between intake man-
ifold and EVAP control system pressure sensor.

• EVAP canister purge volume control 

solenoid valve stuck closed

• EVAP control system pressure sensor 

and the circuit

• Loose, disconnected or improper con-

nection of rubber tube

• Blocked rubber tube
• Cracked EVAP canister
• EVAP canister purge volume control 

solenoid valve circuit

• Accelerator pedal position sensor
• Blocked purge port
• EVAP canister vent control valve