Fault-Code Library · Air metering
P1101: Intake airflow system performance
Measured intake airflow does not match the ECU model across the expected operating range.
Common symptoms
- •Rough idle
- •Hesitation
- •Reduced power
- •Mixture faults
Likely causes
- •Intake leak
- •PCV fault
- •Contaminated MAF
- •Throttle or EGR plausibility problem
First checks
- •Smoke-test intake and PCV circuits
- •Review fuel trims and MAF values
- •Check throttle and EGR command data
Important
P1101 definitions vary by manufacturer; confirm the vehicle-specific description before repair.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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