Hyundai Sonata P0449: Vent Valve Solenoid – Circuit Malfunction

This is a common problem with the Hyundai Sonata Is the Use code P0449. The code refers to a number you receive when your OBD2 scanner scans it. The evaporative emission control (EVAP), system is covered by P0449. It is frequently found alongside, or closely related to, other codes such as P0446, P0420 and P0455.

The P0449 problem is not usually a threat to your Sonata's driveability. Certainly anytime the service engine soon light is on, it’s good to deal with it as soon as possible though. You should also consider: Really good scanner This scanner will allow you to determine if the vent valve operates correctly. This scanner is common in shops. There’s a link towards the bottom the page on exactly how to perform a quality diagnosis with a scan tool.

Hyundai Sonata P0449 Definition

P0449 stands for a universal OBDII Trouble Code. The code can be used to indicate the same things regardless of the make and model of the vehicle (Sonata or otherwise) provided it was produced after 1996.

The P0449 code indicates that the solenoid or valve that controls the evaporation systems isn't working properly. Depending on which vehicle model you have, the EVAP system converts fuel vapor from your gas tank to the intake manifold or charcoal canister. 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.

Hyundai Sonata P0449 OBDII Code Symptoms

A P0449 Code will not usually be associated with other noticeable symptoms. The smell of gas 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.

Fuel vapors are dealt with directly by the EVAP system. If these vapors are leaking from the system, you’ll often smell them faintly while operating the vehicle.

Sonata P0449 Trouble code Causes

P0449 can occur for many reasons in your Hyundai Sonata. 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. You may not need to spend a lot of money replacing the fuel cap if you get this message. fuel cap Try it and let us know if you get rid of it.
• EVAP System Hose– The hose that carries the fuel vapor from the fuel tank to the intake manifold can begin to leak. This can lead to the P0449 error code. You should look for a hole or a tear in the code. This is the main reason for this code. It can be hard to spot the hole without performing a smoke test.
• 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. There are some clips you will need to look for and then remove. Here’s How to check a purge device (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. This could reduce the pressure in your tank and cause you to lose your code. This shouldn't be where you start.
• Fuel Filler Neck– There is often a gasket where the fuel filler neck connects with the gas tank. The gasket may dry out especially if the vehicle is in dry conditions. When it dries out, the fuel tank can’t hold pressure anymore, it may erroneously throw P0449.

Hyundai Sonata Diagnosis - P0449

To diagnose the problem with your Hyundai Sonata's P0449, a mechanic will have a variety of tools at his/her disposal. These are some of the common diagnostics that can be done for the code

• To ensure that the cap can withstand pressure, the mechanic will check it. 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.
• Most mechanics will check for any additional trouble 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. Take a look at the EVAP system. It includes the purge valve and line as well as the 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 Super technical video This is a great article on how to diagnose P0449.

The Most Popular P0449 Fixes

Below are the top Sonata P0449 solutions:

• Replacing the gas cap
• Replacing EVAP lines
• Vent valve replacement
• Wiring repair

You should start with the gas caps and move on to the fuel tanks. This is because the gas caps are the easiest to replace and the least costly.

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

You will need to find the cause of your Hyundai Sonata 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 Sonata’s engine to stop running, it should not be treated lightly. Fuel leaks could be a problem. Check your tank regularly to make sure there is no fuel leaking. You should immediately take it in for repair or replacement.