2019 Infiniti M35 V6-3.5L (VQ35HR) Diagnostic and Repair Information Page 425
YES - GO TO 14.
NO - Repair open circuit, short to ground or short to power in harness or connectors.
14.CHECK A/F SENSOR 1 HEATER
See: P Code Charts/P0031.
Is the inspection result normal?
YES - GO TO 15.
NO - Replace (malfunctioning) A/F sensor 1.
15.CHECK MASS AIR FLOW SENSOR
With CONSULT-III
Check mass air flow sensor signal in "DATA MONITOR" mode with CONSULT-III.
For specification, See: Powertrain Management/Computers and Control Systems/Air Temperature Sensor ( Ambient / Intake )/Specifications.
With GST
Check mass air flow sensor signal in Service $01 with GST.
For specification, See: Powertrain Management/Computers and Control Systems/Air Temperature Sensor ( Ambient / Intake )/Specifications.
Is the measurement value within the specification?
YES - GO TO 16.
NO - Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or ground. See: P Code Charts/P0102.
16.CHECK SYMPTOM MATRIX CHART
Check items on the rough idle symptom in See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Symptom
Related Diagnostic Procedures.
Is the inspection result normal?
YES - GO TO 17.
NO - Repair or replace malfunctioning part.
17.ERASE THE 1ST TRIP DTC
Some tests may cause a 1st trip DTC to be set.
Erase the 1st trip DTC from the ECM memory after performing the tests. See: Powertrain Management/Computers and Control Systems/Testing
and Inspection/Scan Tool Testing and Procedures/On Board Diagnostic (OBD) System/Diagnosis Description.
- GO TO 18.
18.CHECK INTERMITTENT INCIDENT
See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Initial Inspection and Diagnostic Overview/Trouble
Diagnosis For Intermittent Incident/Description.
- INSPECTION END
P0304
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 signal to
vary, ECM can determine that a misfire is occurring.
The misfire detection logic consists of the following two conditions.
1. 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.
2. 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.
