Mass or Volume Air Flow Circuit Malfunction
Air flow measurement is faulty or the circuit has an issue.
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 engine control module (ECM) uses a mass air flow (MAF) sensor to measure the amount of air entering the engine. If the sensor fails or has a wiring issue, the engine can’t adjust the air-fuel mixture correctly, leading to performance problems.
What the computer is actually seeing
The ECM expects a specific voltage from the MAF sensor, usually between 0.5V at idle and up to 4.5V at high flow. A signal outside of this range triggers the code.
What a healthy reading looks like
MAF sensor outputs 0.5V to 4.5V; expected airflow values depend on engine size, typically 1-10 g/s at idle and 50-100 g/s at full throttle.
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.
- 1Inspect the MAF sensor wiring and connectors for damage or corrosion. Repair as needed. Decision point: Is the wiring intact? Yes - Go to next step. No - Repair the wiring.
- 2Clean the MAF sensor with appropriate cleaner. Decision point: Did cleaning improve performance? Yes - Repair done. No - Go to next step.
- 3Measure the voltage output of the MAF sensor while the engine is running. Should be between 0.5V and 4.5V under various throttle positions. Decision point: Is voltage within range? Yes - Test other airflow sources. No - Replace the MAF sensor.
Common causes
- Faulty MAF sensor
- Wiring harness short or open
- Dirty or contaminated sensor
- Vacuum leaks causing incorrect readings
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's usually drivable, but fuel economy and engine performance may be affected.
Will this code come back after clearing?
If the underlying issue isn't fixed, the code will return.
Why would this code pair with other codes?
Related codes often indicate different issues but can affect the same system, like airflow or fuel mixture.
Working a real vehicle right now?
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