P0103

Medium Severity

Mass Air Flow Sensor Circuit High Input

Fuel System

What Does P0103 Mean?

The MAF sensor is reading higher than expected airflow. This causes the engine to run rich. Could be a sensor fault or an intake leak.

Common Fix

Replace MAF sensor

Estimated Cost (DIY)

$40 - $150

Symptoms

  • ⚠️Rich running (black exhaust)
  • ⚠️Poor fuel economy
  • ⚠️Check engine light
  • ⚠️Rough idle

Common Causes

Faulty MAF sensorlikely
Short circuit in MAF wiringpossible
Air leak in intake bootpossible
Aftermarket air filter issuepossible

How to Diagnose P0103

  1. 1Inspect MAF sensor connector
  2. 2Check intake duct for cracks
  3. 3Clean MAF sensor
  4. 4Test MAF output with scan tool

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Related Resources

Repair guides, symptom pages, and wiring diagrams related to P0103.

Frequently Asked Questions

What causes P0103?
Usually a failed MAF sensor or a short in the sensor wiring. Sometimes caused by an oiled aftermarket air filter contaminating the sensor element.
Can an oiled air filter cause P0103?
Yes — oiled aftermarket filters (like some K&N filters) can contaminate the MAF sensor wire, causing false high readings.

Related Repair Guides

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