Mass or Volume Air Flow Sensor A/B Correlation
This code means the PCM/ECM has detected a correlation mismatch between related signals affecting mass or volume air flow sensor a/b. Because airflow is used to calculate fueling, the engine may idle poorly, hesitate, or run with incorrect fuel trims until the fault is repaired.
What You Might Notice
- Check Engine Light illuminated
- Rough idle
- Hesitation on acceleration
- Reduced fuel economy
- Possible stalling
Most Common Causes
- 1
Vacuum leak or air leak in the intake system
- 2
Faulty throttle, MAF/MAP, or related airflow sensor
- 3
Damaged wiring or poor connector contact
- 4
Carbon buildup or sticking throttle body
- 5
PCM/ECM fault
How to Diagnose It
- 1
Check Vacuum leak or air leak in the intake system — Inspect for signs of failure and test before replacing.
- 2
Check Faulty throttle, MAF/MAP, or related airflow sensor — Inspect for signs of failure and test before replacing.
- 3
Check Damaged wiring or poor connector contact — Inspect for signs of failure and test before replacing.
- 4
Check Carbon buildup or sticking throttle body — Inspect for signs of failure and test before replacing.
- 5
Check PCM/ECM fault — Inspect for signs of failure and test before replacing.
How to Fix It
- 1
Inspect the intake tract for leaks or restrictions
- 2
Clean and test the throttle body or airflow sensor
- 3
Repair wiring or connector issues
- 5
Clear the code and verify normal idle and throttle response
Need a deeper diagnosis?
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