Nissan Maxima Service and Repair Manual: P0300, P0301, P0302, P0303, P0304, P0305, P0306 misfire
DTC Logic
DTC DETECTION LOGIC
When a misfire occurs, engine speed will fluctuate. If the engine speed
fluctuates enough to cause the crankshaft
position (CKP) sensor (POS) signal to vary, ECM can determine that a misfire is
occurring.
The misfire detection logic consists of the following two conditions.
- One Trip Detection Logic (Three Way Catalyst Damage)
On the 1st trip, when a misfire condition occurs that can damage the three
way catalyst (TWC) due to
overheating, the MIL 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 MIL will turn off.
If another misfire condition occurs that can damage the TWC on a second
trip, the MIL will blink.
When the misfire condition decreases to a level that will not damage the TWC,
the MIL will remain on.
If another misfire condition occurs that can damage the TWC, the MIL will
begin to blink again.
- Two Trip Detection Logic (Exhaust quality deterioration)
For misfire conditions that will not damage the TWC (but will affect vehicle
emissions), the MIL 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 in any one cylinder or in multiple
cylinders.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform
the following procedure
before conducting the next test.
- Turn ignition switch OFF and wait at least 10 seconds.
- Turn ignition switch ON.
- Turn ignition switch OFF and wait at least 10 seconds.
2.PERFORM DTC CONFIRMATION PROCEDURE-I
- Start engine and warm it up to normal operating temperature.
- Turn ignition switch OFF and wait at least 10 seconds.
- Turn ignition switch ON.
- Turn ignition switch OFF and wait at least 10 seconds.
- Restart engine and let it idle for about 15 minutes.
- Check 1st trip DTC.
3.PERFORM DTC CONFIRMATION PROCEDURE-II
- Turn ignition switch OFF and wait at least 10 seconds.
- Turn ignition switch ON.
- Turn ignition switch OFF and wait at least 10 seconds.
- Start engine and drive the vehicle under similar conditions to
(1st trip) Freeze Frame Data for a certain
time. Refer to the table below.
Hold the accelerator pedal as steady as possible.
Similar conditions to (1st trip) Freeze Frame Data mean that the following
conditions should be satisfied at
the same time.
- Check 1st trip DTC.
CAUTION:
Always drive vehicle in safe manner according to traffic conditions and obey all
traffic laws when
driving.
Driving time varies according to the engine speed in the freeze frame data.
Diagnosis Procedure
1.CHECK FOR INTAKE AIR LEAKAGE AND PCV HOSE
- Start engine and run it at idle speed.
- Listen for the sound of the intake air leakage.
- Check PCV hose connection.
2.CHECK FOR EXHAUST SYSTEM CLOGGING
Stop engine and visually check exhaust tube, three way catalyst and muffler
for dents.
3.PERFORM POWER BALANCE TEST
With CONSULT
- Start engine.
- Perform "POWER BALANCE" in "ACTIVE TEST" mode with CONSULT.
- Check that each circuit produces a momentary engine speed drop.
4.CHECK FUNCTION OF FUEL INJECTOR
- Start engine and let it idle.
- Listen to each fuel injector operation.
Clicking sound should be heard.
5.CHECK FUNCTION OF IGNITION COIL-I
CAUTION:
Perform the following procedure in a place with no combustible objects and good
ventilation.
- Turn ignition switch OFF.
- 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.
- Start engine.
- After engine stalls, crank it two or three times to release all
fuel pressure.
- Turn ignition switch OFF.
- Remove all ignition coil harness connectors to avoid the
electrical discharge from the ignition coils. Refer
to EM-42, "Removal and Installation (LH)" or EM-42, "Removal and
Installation (RH)".
- Remove ignition coil and spark plug of the cylinder to be checked.
- Crank engine for 5 seconds or more to remove combustion gas in the
cylinder.
- Connect spark plug and harness connector to ignition coil.
- . Fix ignition coil using a rope etc. with gap of 13 - 17 mm (0.52 -
0.66 in) between the edge of the spark plug and grounded metal
portion as shown in the figure.
- Crank engine for about 3 seconds, and check whether spark is
generated between the spark plug and the grounded metal portion.
Spark should be generated.
CAUTION:
- Never place the spark plug and the ignition coil within 50
cm (19.7 in) each other. Be careful not to get an electrical
shock while checking, because the electrical discharge
voltage becomes 20 kV or more.
- It might damage the ignition coil if the gap of more than 17 mm
(0.66 in) is made.
NOTE:
When the gap is less than 13 mm (0.52 in), a spark might be generated even if
the coil is malfunctioning.
6.CHECK FUNCTION OF IGNITION COIL-II
- Turn ignition switch OFF.
- Disconnect spark plug and connect a non-malfunctioning spark plug.
- Crank engine for about 3 seconds, and recheck whether spark is
generated between the spark plug and
the grounded metal portion.
7.CHECK SPARK PLUG
Check the initial spark plug for fouling, etc.
8.CHECK FUNCTION OF IGNITION COIL-III
- Reconnect the initial spark plugs.
- Crank engine for about 3 seconds, and recheck whether spark is
generated between the spark plug and
the grounded portion.
Spark should be generated
9.CHECK COMPRESSION PRESSURE
Check compression pressure.
10.CHECK FUEL PRESSURE
- Install all removed parts.
- Release fuel pressure to zero. Refer to EC-592, "Inspection".
- Install fuel pressure gauge kit [SST (J-44321)] and check fuel
pressure.
At idle: Approximately 350 kPa (3.57 kg/cm2, 51 psi)
11.DETECT MALFUNCTIONING PART
Check fuel hoses and fuel tubes for clogging.
12.CHECK IGNITION TIMING
Check idle speed and ignition timing.
13.CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT
- Turn ignition switch OFF.
- Disconnect corresponding A/F sensor 1 harness connector.
- Disconnect ECM harness connector.
- Check the continuity between A/F sensor 1 harness connector and
ECM harness connector.
- Check the continuity between A/F sensor 1 harness connector and ground,
or ECM harness connector
and ground.
- Also check harness for short to power
14.CHECK A/F SENSOR 1 HEATER
15.CHECK MASS AIR FLOW SENSOR
With CONSULT
- Check "MASS AIR FLOW" in "DATA MONITOR" mode with CONSULT.
- For specification, refer to EC-596, "Mass Air Flow Sensor".
With GST
- Check mass air flow sensor signal in Service $01 with GST.
Description
Electric throttle control actuator consists of throttle control motor,
throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The ...
Description
The knock sensor is attached to the cylinder block. It senses engine knocking
using a piezoelectric element. A
knocking vibration from the cylinder block is sensed as vibrational pres ...
Other materials:
Air conditioning cut control
System Diagram
System Description
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM via the CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and
battery voltage.
SYSTEM DESCRIPTION
This system improves engine operation when ...
Center speaker
Removal and Installation
REMOVAL
Remove the center speaker grille, using a suitable tool.
Remove the center speaker screws (A).
Pull out the center speaker (1), disconnect the harness connector
from the center speaker and remove.
INSTALLATION
Installation is in the reverse order of ...
Additional service when replacing TCM
Description
When replacing the TCM, perform the following work.
TCM PROGRAMMING
Since vehicle specifications are not yet written in a new TCM, it
is necessary to write them with CONSULT.
CAUTION:
When replacing TCM, save TCM data on CONSULT before removing TCM.
LOADING AND STORIN ...