Air Filter Restriction Sensor
Signals a restriction in the air intake system, often due to a clogged air filter.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The electronic control unit (ECU) sees that the air intake sensor is reporting a lower airflow than expected, which suggests that the air filter might be dirty or blocked.
What the computer is actually seeing
The air filter restriction sensor detects pressure differences across the air filter. Normal operation shows certain voltage levels, usually around 0.5 to 4.5 volts, corresponding to airflow levels. If the voltage is lower than expected, it indicates restriction.
What a healthy reading looks like
Voltage should be between 0.5V (ideal) to 4.5V (maximum airflow) under normal conditions. Values below 0.5V indicate restriction.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Check the air filter for dirt or damage – replace if necessary. Decision Point: If filter is dirty, replace it and test again.
- 2Inspect the air intake duct for obstructions. Remove any visible blockages. Decision Point: If blockage is found, clear it and retest.
- 3Test the air filter restriction sensor's output voltage with a multimeter while the engine is running. Expected output should be between 0.5V and 4.5V. Decision Point: If voltage is outside expected values, replace the sensor.
Common causes
- Clogged air filter
- Blocked air intake duct
- Faulty air filter restriction sensor
- Damaged wiring or connections
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's moderate severity; you can drive but should address it soon to avoid reduced performance.
Will this code come back after clearing?
If the issue isn't fixed (like a dirty filter), it will likely return.
Why might it pair with other codes?
Other issues in the air intake system can cause similar symptoms, leading to multiple codes.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
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