1. Home
  2. /
  3. Complete List of OBD2...
  4. /
  5. P0104 Code – What...

P0104 Code – What Does It Mean & How To Fix It

This is one of the most frequent OBD2 trouble codes. Read the full article below to know what it means, how to fix it, and what other codes may show related to it.


P0104 is an OBDII trouble code for the Mass or Volume Airflow Circuit and indicates a problem. A key element in measuring and transmitting this information to the engine’s control module is a MAF mass flow sensor, which measures how much air enters the engine.


The P0104 code is triggered when the powertrain control module (PCM) detects that the MAF sensor’s voltage output is out of the expected range. To calculate the correct mixture of air and fuel for efficient engine operation, a PCM uses MAF sensor data.


The P0104 code may be activated for a number of reasons, such as:

  • Faulty MAF Sensor: The code might be caused by a faulty or dirty MAF sensor, which gives inaccurate voltage readings.
  • Wire Problems: The signal from the MAF sensor might be distorted by corroded or damaged wires and connections.
  • Air Intake System Leaks: Unmetered air entering the engine through leaks in the air intake system can affect MAF sensor readings.
  • Clogged or filthy air filter: This factor might restrict airflow and alter the MAF sensor’s results.


You could encounter the following signs and symptoms when the P0104 code is present:

  • The Check Engine Light Is On: The check engine light on the dashboard of the car is the first obvious sign.
  • Diminished Engine Performance: Due to incorrect air-fuel mixture changes, the engine may show diminished power and performance.
  • Rough Idling: If the air-fuel ratio is off, the engine may idle rough or stall.
  • Poor Fuel economy: Inefficient fuel combustion brought on by incorrect MAF sensor readings might result in lower fuel economy.


An OBD-II scanner or a certified mechanic must follow a step-by-step procedure to properly diagnose the P0104 code. Typically, the diagnosis entails:

  • Code reading: Use an OBD-II scanner to get the P0104 code and any associated codes.
  • Visual Inspection: Look for any rust or obvious damage in the wiring and connections of the MAF sensor.
  • Sensor testing: Check the voltage output of the MAF sensor to see if it complies with the manufacturer’s requirements.
  • Check for Leaks in the Air Intake System: Check the air intake system for any leaks that might skew the results from the MAF sensor.

Common mistakes

Dealing with the P0104 error code might result in errors like these:

  • Ignoring the Code: Ignoring the P0104 code and the check engine light might cause the engine to run less well and perhaps endanger other engine parts.
  • Replacing the Sensor Without Proper Testing: Replacing the MAF sensor before making sure it functions properly might result in irrational costs if the real problem is somewhere else.
  • Ignoring Air Intake System Leaks: If the air intake system is not checked for leaks, a proper diagnosis of the issue may not be possible.

How serious is this?

However, the P0104 code is not capable of causing a prompt vehicle breakdown and should not be disregarded. Failure to do so can result in lower engine performance, decreased fuel efficiency, and possible detrimental effects on the engines’ components.

What repairs can fix the code?

repair manuals

Possible fixes for the P0104 error code include:

  • Cleaning or Replacing the MAF Sensor: If the MAF sensor is malfunctioning or polluted, clean it or replace it.
  • Fixing or replacing the wiring and connectors: Take care of any wire and connection problems with the MAF sensor.
  • Repairing Air Intake System Leaks: To stop unmetered air from entering the engine, repair any air intake system leaks.
  • Changing the Air Filter: To guarantee appropriate airflow, change an air filter that is blocked or unclean.

Related codes

Other related codes that may accompany or be triggered by P0104 include:

  • P0100 – Mass or Volume Air Flow Circuit Malfunction
  • P0101 – Mass or Volume Air Flow Circuit Range/Performance Problem


The P0104 DTC code indicates that there may be an issue with the Mass or Volume Air Flow Circuit. The maintenance of optimum engine performance, fuel efficiency, and overall vehicle reliability will be ensured if this problem is resolved in a timely manner. Seek the assistance of a qualified technician who can diagnose and correct the root cause accurately if you notice an engine check light with a P0104 code.

You can take action to maintain the smooth operation of your vehicle without delay if you understand what causes, symptoms, and possible remedies exist for this P0104 code. In order to prolong the life of your vehicle and prevent more serious problems from occurring down the line, it is very important that you regularly carry out maintenance and repairs as soon as possible.

P0104 Code – What Does It Mean & How To Fix It