Chevy Malibu P0449 Code Diagnosis: EVAP System

The most common issue is the Chevy Malibu The Use code P0449. This is your trouble code. It is the reference number given when you connect your Malibu to an a OBDII scanner. It deals with the evaporative emissions management system. This code is often found with or related to P0420,P0446 and, very rarely, P0440.

P0449: Evaporative Emission Control System Vent Valve/Solenoid Circuit Malfunction

Your Malibu's driveability is generally not affected by P0449. Certainly anytime the service engine soon light is on, it’s good to deal with it as soon as possible though. You can also use a scanner to check if your valve is working correctly. Most shops carry them. There’s a link towards the bottom the page on exactly how to perform that procedure. This article will show you how to diagnose and fix the problem.

Chevy Malibu P0449 Definition

The universal OBDII code P0449 can be used to diagnose trouble codes. It means that no matter what make or model vehicle it is, P0449 will always mean "Malibu" regardless of whether the vehicle was made after 1996.

If P0449 is displayed, it means that either the solenoid circuit or the valve controlling the evaporation system are not working correctly. Depending on your vehicle's model, the EVAP cycle fuel vapor out of the tank into an intake manifold. This system can fail to properly deal with fuel vapor if it malfunctions.

ECM (Engine Control module) has identified a problem in the circuit that controls the vent which releases fuel vapor. Soon, the service engine will follow this up.

Chevy Malibu P0449 OBDII Code Symptoms

The P0449 code is usually not accompanied with any other symptoms than those listed. The smell of gas And the service engine soon light. The slightest drop in fuel economy may also be noticeable.

The fuel tank and fuel filler tubes should smell particularly strong.

The EVAP process deals with fuel vapors directly. If these vapors are leaking from the system, you’ll often smell them faintly while operating the vehicle.

Malibu P0449 Trouble Code Causes

The P0449 code can be triggered by many factors in Chevy Malibu. These are some of the more common issues that can trigger the P0449 code. Here's a video explaining the process.

• Fuel Cap– A bad fuel cap can cause the code to be thrown for sure. Often, you’ll get a message informing you that the fuel cap is off even when it is on. It may be worth your time to get that message and a P0449 to ensure you don't waste any money.
• EVAP System Hose– The hose that carries the fuel vapor from the fuel tank to the intake manifold can begin to leak. The P0449 code will be generated. It should have a hole or tear. This is the leading cause of code.
• Vapor Canister Purge Valve– One of the most common causes of the P0449 code is the vapor canister purge valve. It’s really easy to replace. You will need to locate and take out a few clips. Here’s How to test a purge valle (YouTube).
• Trouble with Fuse/Wiring– If the wiring going to the valve has been compromise, it’ll lead to the P0449.
• Fuel Tank Sending Unit– It is possible for the gasket that attaches the fuel sending unit to the gas tank to go bad. It could cause a drop in tank pressure or throw the code.
• Fuel Filler Neck– There is often a gasket where the fuel filler neck connects with the gas tank. It is possible for this gasket to dry, particularly if vehicles spend a lot of time in dry environments. When it dries out, the fuel tank can’t hold pressure anymore, it may erroneously throw P0449.

P0449 Chevy Malibu Diagnosis

The mechanic can use a range of tools to determine the cause of your Chevy Malibu P0449. The most commonly used methods to diagnose this code are:

• A mechanic will examine the gas cap and verify that it is able to withstand high pressure. If you are getting a warning that your gas cap is off, even when it’s on, replacing it will more than likely clear this code.
• The mechanic will check for other codes. It is easier to diagnose problems if there are more codes. That’s because when they appear together in certain combinations, there will often only be only a few conditions that will throw any combination of codes at one time.
• The mechanic will normally determine what problem codes are associated with P0449. Check out the EVAP System. It includes the line, purge valve and canister.
• Monitor and check the pressure in your fuel tank.
• After for the checks and fixes listed above, the mechanic will perform two tests: A smoke test, and they’ll use a scan tool to confirm that the EVAP solenoids and valves are operating properly.

Are you still having problems? Here’s a Video with super technical content This is a great article on how to diagnose P0449.

The Most Popular P0449 Fixes

These are some of the more common Malibu P0449 solutions:

• Replacing the gas cap
• Replacement for EVAP Line
• Vent valve replacement
• Wiring repair

It is best to begin with the gas cap, and then work your way up to the fuel tanks. The gas cap is the most difficult and cost-effective item to replace.

Here’s a great video on How to check your gas cap.

We wish you all the best in finding out why your Chevy Malibu is throwing the P0449 code. We trust this helped. You can add any additional information by leaving a comment.

Do you consider P0449 to be a serious concern?

While P0449 is not going to cause the Malibu’s engine to stop running, it should not be treated lightly. There could be fuel contamination. You should pay extra attention to the level of your fuel tank and ensure that you're not leaking fuel. It is best to have it checked and/or dealt with immediately.