P0449 Error Code - What Does it Mean?

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So, you’ve scanned your vehicle and it has returned an error code P0449 and you want to deepen your understanding of what it means?

We’ll you’ve come to the right place because it is actually simpler to understand than you think.

In this article we are going to go through the causes, symptoms, diagnosis and potential solutions for error code P0449 do keep reading!

Possible Causes of Error Code P0449

No matter what the specific cause is, this code means that there is a leak found within the EVAP system of your vehicle.

The EVAP system exists to help prevent the escape of fuel vapors from within your vehicle. This contributes to pollution and smog, even when your car is not being used. Read more about the EVAP system in this article: Is it Ok to Drive with EVAP Leak?

Below is a list of the most common reasons and the general explanation of old why it may cause this error code to pop up in your car.

Missing Fuel Cap

By far, the most common reason that people receive an error code like this is that they forgot to place the top on the gasoline tank when they finish filling up at the gas station.

If the check engine light came on for the first time after leaving the gas station, then there is a good chance that you forgot to screw the lid on before leaving. Check this first.

Loose Fuel Cap

Sometimes you may find that the lid to the fuel tank is still on; however, it may not have been screwed on tightly enough to prevent any vapors from escaping.

Anytime you refill your vehicle, you need to ensure that whenever you replace the fuel tank’s lid, it is screwed on as tightly as possible to prevent this error code.

Damaged Fuel Cap

Is your fuel cap screwed on as tight as possible? Still experiencing a P0499 error code?

This means you may need to consider the possibility that the lid of your fuel tank has been damaged.

If it is no longer entirely leakproof, then you may get one of these error codes. Luckily, it is inexpensive to replace.

Faulty Electronics or Wires

Occasionally, the error code will display erroneously. This is typically caused by the fraying of wires or an issue with some of the electronic components from within your vehicle used to measure vapors’ escape.

If they begin to malfunction, they may send the signal to your vehicle that it is leaking whenever it is not and because the error code appears.

Damaged Fuel Tank

Of course, it is always possible that while you were driving, your vehicle’s fuel tank was punctured.

Furthermore, it does not necessarily need to be an incredibly large hole for it to cause this error code. Any sized hole inside the fuel tank of your vehicle will cause fuel vapors to escape and cause error code P0449.

EVAP Hose Leaks or Damage

Many hoses are used throughout the chassis of your vehicle as part of the EVAP system. Over time these will wear down, and occasionally they may develop some leakage.

EVAP Vent Damage

Finally, one last potential cause would be damage to the charcoal canister vent.

This is where the fuel vapors from your vehicle are absorbed by activated charcoal.

Error Code p0449 Symptoms

Below are some of the symptoms you may experience if there is a leak in your EVAP system that will cause the P0449 error code.

Strong smell of fuel

One of the best ways of distinguishing a problem related to error code P0449, without scanning the OBD II ports, is from a strong smell of gasoline.

If you smell gasoline inside or outside of your car, even when the fuel cap is tightly fastened, your vehicle may suffering from complication related to this error code.

Check Engine light is on

Most of the time a driver will not notice any problem with their vehicle until they see the check engine light come on.

If you notice that the check engine light has turned on, it is a good time to scan it with an OBD II port scanner (assuming you have one). If you don’t have a scanner, check for the other symptoms and take your car to a mechanic to scan.

Issues with Fuel Economy and performance

If your fuel system is no longer securely sealed, you will consistently leak gasoline. So, if you notice that you are filling up more regularly or you are experiencing a drop in performance you may have a leak.

Final Thoughs on P0449 Symptoms

Even though your vehicle has the check engine light on, you may notice no drivability issues. If this
problem is a small leak, it can take an incredibly long time to notice anything.

While it is still technically safe for you to drive if your issues are related to this error code, it is important to get it fixed rapidly. The longer you leave it, the more pollutants your car will release.

How to Diagnose and Solve P0449 Error Code

If you believe that you are experiencing complication related to this error code, this guide will allow you to diagnose the issue without the help of a mechanic.

Total Time Needed :


Minutes (depending on your level of knowledge)

Required Tools:

- OBD II scanner
- Pressure gauge

These short steps may help to diagnose and treat issues arising from error code P0449:

Scan Your Vehicles to Make Sure Error Code P0449 Is The Only Error:

The very first thing that you need to do is get an OBD II port reader and scan your vehicle’s port.

Hopefully, you will only receive back one error code. If multiple, you will need to find out what each of them indicate and keep problem solving from there.

Check your Fuel Cap for Damage:

If P0449 was the only error code that you found, the first thing we recommend doing is checking the lid of your fuel tank. As stated earlier, the most common cause of this specific error code is whenever people forget to replace the lid of their fuel tank.

It could also be damaged or not screwed on tightly enough.

Solution: Replace The Gas Cap Of Your Vehicle

If there is any damage to the cap which could cause a leak, replace it.

Check EVAP Hoses For Cracks Or Damage:

It is also a good idea to examine the hoses of your vehicle’s evaporative emission control system. This error code may appear due to damage or the formation of cracks are forming on these hoses.

Solution: Replace the Hoses of Your Vehicles EVAP System

Simply, replacing the hoses inside of your vehicle that are damaged or worn will ensure that no leaks are coming from there.

Check Charcoal Vent and Canister:

The reverse valve on the charcoal vent could be either blocked or damaged. It should be
easy for you to tell whether this part needs to be replaced once you have located and inspected it.

Look for any potential damage to the charcoal canister.

Solution: Fix the Charcoal Canister and the Charcoal Vent

Whatever issues you find, you will either need to repair of fix the damage to eliminate the error code.

Check for Damage to The Vehicle’s Fuel Tank:

Any breach of the integrity of your vehicle’s fuel tank will cause this error code. Do a thorough inspection to identify any holes or potential leaks.

Solution 1: Repair any Damage to The Vehicle’s Fuel Tank

Solution 2: Check your Fuel Tanks pressure:

This is more of a final check once you have implemented the above fixes or resolved what may have been causing error code P0449.

Regardless, you will need to use a pressure gauge to measure the fuel tanks pressure. If this issue has
been repaired and then the pressure should stay consistent over time.

If it has not been repaired, you will notice that it the pressure fluctuates the longer that you let it sit.

Final Notes About the P0449 Error Code

It is common to get a little nervous whenever the check engine light turns on.

Regardless, if the light has turned on due to error code P0449 there is little need to panic. This error code relates to a leak in your EVAP system and will not directly impact your personal safety.

Look out for the symptoms indicated above and go through the steps I have outlined to help you identify the source of the leak.

While it can be difficult to find the exact source of the leak, it is a relatively minor issue. Despite this, it is important to repair the leak in order to prevent pollution and unnecessary fuel expenses.

It is always helpful in these cases to enlist the help of an experience mechanic who can use their knowledge to find and repair the leak fast.

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