2019 Infiniti M35 V6-3.5L (VQ35HR) Diagnostic and Repair Information Page 438
Check the initial spark plug for fouling, etc.
Is the inspection result normal?
YES - Replace spark plug(s) with standard type one(s). For spark plug type, See: Maintenance.
NO - Repair or clean spark plug. Then GO TO 8.
8.CHECK FUNCTION OF IGNITION COIL-III
1. Reconnect the initial spark plugs.
2. Crank engine for approximately 3 seconds, and recheck whether spark is generated between the spark plug and the grounded portion.
Spark should be generated.
Is the inspection result normal?
YES - INSPECTION END
NO - Replace spark plug(s) with standard type one(s). For spark plug type, See: Maintenance.
9.CHECK COMPRESSION PRESSURE
Check compression pressure. See: Engine, Cooling and Exhaust/Engine/Compression Check/Testing and Inspection.
Is the inspection result normal?
YES - GO TO 10.
NO - Check pistons, piston rings, valves, valve seats and cylinder head gaskets.
10.CHECK FUEL PRESSURE
1. Install all removed parts.
2. Check fuel pressure. See: Engine, Cooling and Exhaust/Engine/Tune-up and Engine Performance Checks/Fuel Pressure/Testing and
Inspection.
Is the inspection result normal?
YES - GO TO 12.
NO - GO TO 11.
11.DETECT MALFUNCTIONING PART
Check fuel hoses and fuel tubes for clogging.
Is the inspection result normal?
YES - Replace "fuel filter and fuel pump assembly".
NO - Repair or replace malfunctioning part.
12.CHECK IDLE SPEED AND IGNITION TIMING
Check idle speed and ignition timing.
For procedure, See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Initial Inspection and Diagnostic
Overview/Basic Inspection.
For specification, See: Engine, Cooling and Exhaust/Engine/Tune-up and Engine Performance Checks/Idle Speed/Specifications and See: Engine,
Cooling and Exhaust/Engine/Tune-up and Engine Performance Checks/Ignition Timing/Specifications.
Is the inspection result normal?
YES - GO TO 13.
NO - Follow the See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Initial Inspection and Diagnostic
Overview/Basic Inspection.
13.CHECK AIR FUEL RATIO (A/F) SENSOR 1 INPUT SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect corresponding A/F sensor 1 harness connector.
3. Disconnect ECM harness connector.
4. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
5. Check the continuity between A/F sensor 1 harness connector or ECM harness connector and ground.
