What Is a P0102 OBDII Code and What are the Fixes?

The official error code is labeled as a “Mass or VAF A Ckt Low Input.”

The MAF sensor regulates the flow of air into an engine to keep the air/fuel ratio at an optimal level.

It measures the amount of air going into an engine and sends the information to the onboard computer (ECM/PCM).

When there is no information or sporadic information, the ECM will send out a P0102 OBDII Code.

What Is a P0102 OBDII Code?

A P0102 OBDII code is a “Mass or VAF A Ckt Low Input” error.

The MAF sensor is located on the air filter box or throttle body and measures airflow going into an engine.

A P0102 OBDII Code indicates there is an error with the MAF, and airflow information is not getting received by the onboard computer.

P0102 OBDII Code Symptoms

• Rough Idle
• Stalling

Symptoms can vary greatly from no symptoms to rough idle and stalling.

What symptoms appear depends if the MAF has failed completely or it is dirty and so on.

What Causes a P0102 OBDII Code?

• Dirty Mass Airflow Sensor
• Bad Mass Airflow Sensor
• Blown Fuse
• Wiring or Bad Harness
• Vacuum Leak
• Restricted Exhaust such as Clogged Catalytic Converter

Mass Airflow Sensor Location

The MAF (Mass Airflow Sensor) will be located below the air filter.

It is often combined with the air filter box. The air passes the air filter and then passes the MAF sensor.

They are usually easy to locate and replace if necessary.

Common Causes and Fixes for a P0102 OBDII Code

1. Check the Fuses


The first step is to check for any blown fuses.

If you can find the fuse for the mass airflow sensor be sure it is good.

If you cant find the fuse check them all for any bad ones.

2. Check the Wiring


Check the wiring going to the MAF sensor for any loose connections.

Sometimes unplugging the harness and plugging it back in can solve issues.

3. Clean the Mass Airflow Sensor


If the air filter on a vehicle is not changed regularly, the MAF sensor can become dirty with debris.

The MAF Sensor can be cleaned with MAF Sensor cleaner and is a common method to get a P0102 error to clear.

The cleaner can be bought at auto parts stores or online on Amazon or eBay.

4. Test or Replace the MAF Sensor


Replacing the MAF sensor is usually easy to do by removing the wire harness and screws.

A new sensor will be needed which can be bought at an auto parts store or online.

Can I Drive with a P0102 OBDII Code?

Some car and trucks will be drive-able while other will not.

If the sensor has failed completely, the vehicle will likely not be drive-able.

If the sensor just needs to be cleaned up and is dirty, the vehicle may drive with no issues.

How much information the onboard computer is getting about airflow into the engine will be the cause of the engine running rough or not.

How To Diagnose a P0102 OBDII Code

A P0102 OBDII will display an engine light, and an OBDII scan tool can be used to read the error code.

Some cars and trucks will also need an OBDII scan tool to clear the code.

If you do not have a scan tool, there are many low-cost options.

Many auto part stores will often have loaner tools that can also be used in some locations.

Cost to Diagnose and Repair a P0102 Code

The repair cost for a P0102 Code is usually not high, with the replacement part usually a low-cost item.

This can, of course, vary between manufacturers, so be sure to look up a replacement online for the cost of a replacement MAF sensor.

Labor should also be low cost as it is a quick job to replace a MAF.

If the problem is in the wiring, the cost may get higher depending on how long t takes to find the shorted or open wire.

Replacing or cleaning the sensor is usually an easy DIY job that falls into the backyard mechanics ability.

Summary
If you run an OBDII scan on your vehicle and get a P0102 Code, it is showing an error with the MAF sensor.

The MAF sensor measures the airflow as it goes into an engine and sends the data to the ECM.

The ECM uses the data to get the right mixture of gas and air into a cylinder.

The error is usually an easy fix by either cleaning or replacing the MAF sensor.

Sometimes the error can be caused by a blown fuse or an electrical problem.

Be sure to check the harness and wiring that plugs into the MAF sensor as a loose or bad connection will cause a problem.