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 Nissan-Datsun Sentra SE-RFACTORY OEM SERVICE PROCEDURE
With CONSULT-II
WARNING: This page is about a different car, the 2005 Nissan 350Z. However, it is still accessible from the selected car via links, so may be relevant.
- Reconnect all harness connectors disconnected.
- Start engine and warm it up to normal operating temperature.
- Connect CONSULT-II and select "DATA MONITOR" mode.
- Select "MAS A/F SE-B1" and check indication under the following conditions.CONDITION AND MAS A/F SE-B1 (V) CHART
Condition MAS A/F SE-B1 (V) Ignition switch ON (Engine stopped.) Approx. 0.4 Idle (Engine is warmed-up to normal operating temperature.) 0.9 - 1.2 2, 500 rpm (Engine is warmed-up to normal operating temperature.) 1.5 - 1.9 Idle to about 4, 000 rpm(1) 0.9 - 1.2 to Approx. 2.4 (1) Check for linear voltage rise in response to engine being increased to about 4, 000 rpm. - If the voltage is out of specification, proceed the following.
- Check for the cause of uneven air flow through mass air flow sensor. Refer to following.
- Crushed air ducts
- Malfunctioning seal of air cleaner element
- Uneven dirt of air cleaner element
- Improper specification of intake air system parts
- If NG, repair or replace malfunctioning part and perform step 2 to 4 again.
If OK, go to next step.
- Check for the cause of uneven air flow through mass air flow sensor. Refer to following.
- Turn ignition switch OFF.
- Disconnect mass air flow sensor harness connector and reconnect it again.
- Perform step 2 to 4 again.
- If NG, clean or replace mass air flow sensor.
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
