2019 Infiniti M35 V6-3.5L (VQ35HR) Diagnostic and Repair Information Page 474
1. Start engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Start engine and keep the engine speed between 3,500 and
4,000 rpm for at least 1 minute under no load.
6. Let engine idle for 1 minute.
7. Open engine hood.
8. Check the voltage between ECM harness connector terminals under the following condition.
Is the inspection result normal?
YES - INSPECTION END
NO - Go to See: P Code Charts/P0420.
Diagnosis Procedure
1.CHECK EXHAUST SYSTEM
Visually check exhaust tubes and muffler for dents.
Is the inspection result normal?
YES - GO TO 2.
NO - Repair or replace malfunctioning part.
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 1.
Is exhaust gas leak detected?
YES - Repair or replace malfunctioning part.
NO - GO TO 3.
3.CHECK INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected?
YES - Repair or replace malfunctioning part.
NO - GO TO 4.
4.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,
