Toyota Rav4 P0455: EVAP System → Leak Detected (Large)

The most frequent trouble code with the Toyota Rav4 The Code P0455. The trouble code refers to a number you receive when your Rav4 is plugged into an OBD2 scanner. It has to do the emission system. If there are any problems, P0455 indicates they have been fixed. Leakage large In the evaporative emissions control system (EVAP). This code is often found with or related to other codes such as P0420 and P0430.

P0455: EVAP System → Leak Detected (Large)

The P0455 issue is not usually a threat to your Rav4's driveability. Certainly anytime the service engine soon light is on, it’s good to deal with it as soon as possible though.

Toyota Rav4 P0455 Description

P0455 refers to a general OBDII trouble code. It means that no matter what make or model vehicle you have, this code will still mean the exact same thing (Rav4 and not). 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 Toyota Rav4’s EVAP system, it will throw the P0455 OBDII Code.

Toyota Rav4 OBDII code Symptoms

The P0455 code is usually not accompanied with any other symptoms than those listed. The smell of gas The service engine soon light. It is possible to notice a slight dip in fuel economy.

Particular attention should be paid to the fuel tank or fuel filler tube smell.

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.

Causes of Rav4 P0455 Problem Code

P0455 code can be triggered in Toyota Rav4 by many factors. The most frequent problems that trigger this code are:

• Hose for Evap System– 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. This could cause a drop in tank pressure which can throw off 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. It may be worth your time to get that message and a P0455 to ensure you don't waste any 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 Diagnostics- Toyota Rav4

To diagnose the problem with your Toyota Rav4's P0455 code, a mechanic can use a variety of tools. These are some of the common diagnostics that can be done for the code

• A mechanic will often check for additional 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.
• Once the mechanic has determined the trouble codes associated with P0455, he or she will usually 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.
• Monitor and check the pressure in your fuel tank.
• 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 Toyota Rav4, 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

Below are the top Rav4 P0455 solutions:

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

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 test your gas tank.

You will need to find the cause of your Toyota Rav4 throwing the code P0455. This should help. You can add any additional information by leaving a comment.

Are P0455 Serious Concerns?

While P0455 is not going to cause the Rav4’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.