Volkswagen Jetta P0455 Code Diagnosis

The most frequent trouble code with the Volkswagen Jetta Is the Code P0455. This code is used to refer to the number given when your Jetta is connected to an OBDII scanner. If there's a problem, P0455 means that it is. Leakage large It is part of the evaporative emission controller system. It is frequently found in conjunction with other codes such as P0420 or P0441.

The P0455 issue is not usually a threat to your Jetta's driveability. Certainly anytime the service engine soon light is on, it’s good to deal with it as soon as possible though. It's often associated with P0442. See Volkswagen Jetta P0442 OBDII Code for more.

Volkswagen Jetta P0455 Definition

The universal OBDII code P0455 can be used to diagnose any problem. It means that no matter what make or model vehicle you have, this code will always mean the same (Jetta or otherwise). Technically, the code stands for:

System Gross Leak – Evaporative Emission System

The EVAP captures any fuel vapor in the fuel tank. They are then sent to the engines intake for ignition. When there is a large leak in the Volkswagen Jetta’s EVAP system, it will throw the P0455 OBDII Code.

Volkswagen Jetta P0455 OBDII Code Symptoms

A P0455 Code will usually not cause any symptoms except the ones listed below. The smell of gas The service engine soon light. It is possible to notice a slight dip in fuel economy.

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

The EVAP system is responsible for fuel vapors. If these vapors are leaking from the system, you’ll often smell them faintly while operating the vehicle.

Jetta P0455 Trouble Code Causes

P0455 Trouble code in Volkswagen Jetta can trigger for many reasons. These are some of the more common issues that can trigger the P0455 code in your Volkswagen Jetta:

• 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 P0455 code. You should look for a hole or a tear in the code. This is the main problem that can cause the code.
• Vapor Canister Purge Valve– One of the most common causes of the P0455 code is the vapor canister purge valve. It’s really easy to replace. You will need to locate and take out a few clips.
• The Faulty Charcoal Caister– The charcoal canister is often the cause of P0455.
• Fuel Tank Sending Unit– It is possible for the gasket that attaches the fuel sending unit to the gas tank to go bad. It can lower the tank pressure, which could throw out the code.
• 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 get the message but a P0455. This will save you time and money.
• 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.

P0455 Diagnosis- Volkswagen Jetta

The mechanic can use a range of tools to determine the cause of your Volkswagen Jetta's P0455. These are some of the common diagnostics that can be done for the 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 trouble codes are associated with P0455. Take a look at the EVAP system. It includes the purge valve and line as well as the canister.
• 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.
• Monitoring and checking the fuel tank pressure is a must.
• The mechanic will then perform the following tests after completing the above-mentioned checks:
• A smoke test, and they’ll use a scan tool to confirm that the EVAP solenoids and valves are operating properly.

Here’s a pretty good video on diagnosing these leaks from Scotty Kilmer, if you are interested:

While the trouble code may state that there is a “large leak” in the EVAP system of your Volkswagen Jetta, the actual leak will most likely still look rather small. The “large” really is referring to how much pressure is being lost.

Most common P0455 fixes

These are some of the most popular Jetta P0455 solutions:

• Replacement of gas cap
• Replacement for EVAP Line
• Replace charcoal canister
• Change the fuel tank

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 test your gas tank.

It's a good idea to try and figure out why your Volkswagen Jetta is throwing the P0455 code. This information is hoped to be helpful. You can add any additional information by leaving a comment.

Are P0455 Serious Concerns?

While P0455 is not going to cause the Jetta’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. It is best to have it checked and/or dealt with immediately.