Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2004 Infiniti Q45FACTORY OEM SERVICE PROCEDURE
7. Check Mass Air Flow Sensor
With CONSULT-II
- Install all removed parts.
- Check "MASS AIR FLOW" in "DATA MONITOR" mode with CONSULT-II.
- 3.8 - 5.2 g.m/sec: at idling
- 16.0 - 21.5 g.m/sec: at 2,500 RPM
With GST
- Install all removed parts.
- Check mass air flow sensor signal in MODE 1 with GST.
- 3.8 - 5.2 g.m/sec: at idling
- 16.0 - 21.5 g.m/sec: at 2,500 RPM.
OK or NG
OK: GO TO 8.
NG: Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or grounds. Refer to DTC P0101 MAF SENSOR .
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.