If you have a P1101 Chevy Malibu trouble code, it means your mass airflow sensor (AKA MAF sensor) is out of test range.
So what the hell does that actually mean?
In simple terms, it means the system that draws in fresh air into your Chevy Malibu’s engine has a problem.
As with many trouble codes, there are several possible reasons why you are getting the code. In this article, we’ll take a look at different reasons why your Malibu is getting a P1101 code and help you discover which one is causing your problem.
What is a mass air flow sensor?
Let’s begin with a quick overview of what a mass air flow sensor is.
Most of you know how an engine works, but if you don’t… check out this great overview by Car and Driver Magazine.
Now that we’re all up to speed on how an engine works, you know that an engine needs air in order to create combustion in the cylinders. Your air intake system does just what it sounds like – it takes in the air your engine needs to operate.
What your Chevy Malibu’s mass airflow sensor does is monitor the flow of air going into your engine.
When it detects too much air or too little air, your mass airflow sensor sends an alert to your Malibu’s computer, which then alerts you of the problem via the check engine light.
P1101 Chevy Malibu Trouble Code Causes
Let’s now take a look at the main causes for a P1101 trouble code on your Chevy Malibu. There are several possible causes, so you’re going to have to do a little bit of detective work to find it.
Go through this list one-by-one. If one solution doesn’t work, move on to the next.
NOTE: Be sure to give your Malibu some time to reset the check engine light after you try a fix. It should reset on its own after about 20 minutes of driving.
Dirty Air Filter
If you haven’t replaced or cleaned your Chevy Malibu’s air filter in a long time, it could be causing the P1101 trouble code.
Your air filter catches debris and prevents it from getting sucked into your engine. Over time, your filter gets clogged up and restricts the flow of air into your engine.
When this happens, your engine becomes air starved and it can’t deliver the precise amount of air to your engine’s cylinders for combustion.
Dirty Throttle Body
It’s common for the throttle body to get gunked up in a Chevy Malibu.
For those of you not familiar with what a throttle body does, learn all about it in this article from Haynes.
A dirty throttle body is especially likely to happen if your air filter is dirty. A dirty air filter could be allowing crap to pass through the air intake system. Said crap gets into your throttle body and gunks up the butterfly valve, restricting its movement.
Because your throttle body is struggling to work properly, the airflow into your engine can be restricted. This can cause the P1101 Chevy Malibu trouble code.
To fix this problem, all you need is a bottle of throttle body cleaner and a little mechanical courage to access your throttle body. Here’s a great short video that shows you how to do it:
Your air intake system sucks. LIterally.
So if there’s a leak anywhere in the system, it’s going to impact air flow. And when there’s a problem with air flow, you know what can happen – a P1101 trouble code.
So how do you find a vacuum leak?
Start by looking for it. Maybe there’s a crack or a hole in a hose that you can see. If you can’t see anything, use your ears…
You can often hear a vacuum leak. It will make a hissing noise at the source of the leak. So open your hood while the car is running and take a listen. This isn’t always easy to do because your engine makes a lot of noise and it could be hard (or impossible) to hear the leak.
Some people find vacuum leaks by spraying carburetor cleaner in the suspected areas. When the carburetor cleaner gets sucked in by the leak, there will be a change in the car’s idle. I don’t recommend doing this because there’s a chance the carburetor cleaner can start a fire on your engine. And an engine fire is no fun.
A great way to find a leak is to use a smoke machine. What you do is pump smoke into your car’s engine while it’s not running. If you have a leak, you’ll see smoke coming out of it.
Smoke machines built for engine diagnostics can be expensive. If you’re looking for a hack, you can try using a cigar. Love him or hate him, here’s a video by the legendary Scotty Kilmer that shows how to do the cigar hack:
While we’re on the topic of vacuum leaks, a very common source for a leak in a Chevy Malibu is a damaged O-ring seal in the charge air cooler coupler (the part that connects the air duct to the throttle body).
This problem is so common that General Motors has issued a service bulletin on the issue. Click here to see GM Service Bulletin PIP5402D.
Dirty Mass Air Flow Sensor
Another reason why you might be getting a P1101 code is a dirty mass air flow sensor.
Just like with a gummed up throttle body, contaminants that come through a dirty air filter can get on your mass air flow sensor and make it malfunction.
Cleaning your mass air flow sensor is easy. Just be sure to use a mass air flow sensor cleaner. Yes, mass air flow sensor cleaner is an actual thing and it’s what you should use. Your mass air flow sensor is very delicate and this cleaner will not damage the sensors on it.
Some people might tell you it’s OK to use a carburetor cleaner or throttle body cleaner to clean your mass air flow sensor.
Don’t listen to them. These other cleaners can leave residue behind that could damage your mass air flow sensor. Use the proper cleaner for the job!
Clogged PCV Orifice
Another common reason for a P1101 Chevy Malibu trouble code is a clogged PCV orifice. It is so common that General Motors issued a service bulletin – number 20-NA-047.
The P1101 code is thrown because your Chevy Malibu’s computer detects higher than normal pressure in the engine’s crankcase. This can be happening because there is a blockage in your Malibu’s air intake system or a blockage in the PCV orifice.
Bad Mass Air Flow Sensor
If all else fails, you just might have a bad mass air flow sensor.
Before buying a replacement part, be sure to inspect your mass air flow sensor’s connections. Make sure it is connected and that the wires going to it are not damaged. If everything looks good, it might be time to replace the sensor.
Replacing this part is very easy to do on a Chevy Malibu. Here’s quick video that shows how to do it:
If your Chevy Malibu is throwing a P1101 trouble code, It means your Malibu has a problem with its air intake system. The solution is usually easy to fix. Things like cleaning your throttle body, replacing your air filter, or repairing a vacuum leak will clear the code and get you back on the road.