3 Common Causes and Fixes P1101 Chevy Malibu

Causes include the MAF sensor, throttle body, and a possible vacuum leak.

What is a P1101 on a Chevy Malibu?

A P1101 OBDII error code is listed as “MAF Out of Self Test Range.”

Some scan tools will give the error as an “Intake Air Flow System Performance.”

When the Chevy Malibu first starts, the mass airflow sensor (MAF) does a self-diagnostic test.

If the self-diagnostic test results are out of range, a P1101 error code is given.

There is usually an issue with the MAF sensor, throttle body, or a vacuum leak.

3 Common Causes and Fixes P1101 Chevy Malibu

• Mass Airflow Sensor (MAF)


A bad or dirty mass airflow sensor can cause a P1101 error code.

The mass airflow sensor is located at the air intake filter box and is easy to clean or replace.

It is usually best to clean the sensor first before replacing it as they are often just dirty.

A can of Mass Airflow Sensor cleaner can be bought at most any auto part store which can be used to clean the MAF sensor.

• Throttle Body


If the throttle body has failed or becomes dirty, it can give a P1101 code.

It is located at the back of the engine up against the firewall with the air intake hose attached.

If it is dirty, it can be cleaned up with throttle body cleaner and a rag.

Sometimes it will look clean but has dirt somewhere that requires it to be cleaning.

It may have also failed but cleaning it up often solves throttle body issues.

• Vacuum Leak

A vacuum leak can cause many different issues, including a P1101 error code.

If a leak is big, it can often be heard, but small leaks can be hard to find.

A spray bottle can be used to see if the idle changes when the leak is sprayed to help pinpoint the location.

A mechanic shop will use a smoke machine that feeds smoke into the system and comes out of the leak helping to find it.

A common weak point is the PVC valve which depending on the Chevy Malibu year, may have two.

Often if the PVC valve has gone bad, it will make a hissing noise.

Summary
The Chevrolet Malibu is a great car, but like all vehicles can have issues, especially as it ages.

One such common issue is a P1101 OBDII error code.

If the check engine light comes on and a code reader gives a P1101 trouble code, it is usually the mass airflow MAF, throttle body, or a leak.

The first thing to check is how dirty the throttle body is, and clean it if necessary.

Often they can look clean but have dirt or grim somewhere that is causing an issue.

To clean it use throttle body cleaner; it can be sprayed and cleaned up with a rag.

Depending on how dirty it is, it may need to be removed and cleaned very well.

An air leak can also cause issues, with large leaks usually easy to find and mall leaks harder.

For hard-to-find leaks, certified mechanics will use a smoke machine that feeds smoke into the system and comes out of the leak location.

The mass airflow sensor reference voltage can also be checked along with fuel pressure, air leaks, vacuum system, fuel trim system, if the system is too lean, and self-test range.