Dodge Durango P0456: EVAP System – Small Leak

This is one of the most commonly encountered trouble codes for the Dodge Durango The Code P0456. The trouble code refers to a number you receive when your Durango is plugged into an a OBDII scanner. A P0456 code indicates that there may be a slight leakage in the evaporative exhaust control system. It is sometimes found along with other codes such as P0420 or P0441.

The P0456 problem is not usually a threat to your Durango's driveability. Certainly anytime the service engine soon light is on, it’s good to deal with it as soon as possible.

While the trouble code may state that there is a “small leak” in the EVAP system of your Dodge Durango, it is actually referring to the amount of pressure lost, and not the physical size of the leak. They can also be very minor.

Dodge Durango P0456 Definition

The universal OBDII code P0456 can be used to diagnose any problem. It means that no matter what make or model vehicle you have, this code will be the same (Durango and not). Technically, the code stands for:

System Leakage in the Smallest Detail – 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 small leak in the Dodge Durango’s EVAP system, it will throw the P0456 OBDII Code. If there is a large leak, it’ll throw P0455.

Dodge Durango P0456 OBDII Code Symptoms

The P0456 code is usually not accompanied with any other symptoms than those listed. Smells like gas The service engine soon light.

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. But, it won’t affect the way the engine itself runs. The EVAP system is for fuel vapor and does not affect the Durango's engine.

Durango P0456 Troublecode Causes

P0456 can happen for many reasons in your Dodge Durango. If your Durango has warned you at all in the last few months that the fuel cap was off when it wasn’t, then replacing it would be a great first step.

These are some of the most frequent problems that can throw off the code. They're listed in alphabetical order, from the most likely to the least.

• Hose for Evap System– The hose that carries the fuel vapor from the fuel tank to the intake manifold can begin to leak. The P0456 error code will be generated. It should be checked for tears or holes. This is the leading cause of code.
• Vapor Canister Purge Valve– One of the most common causes of the P0456 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.
• 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 P0456 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. 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.

Dodge Durango Diagnostics - P0456

The mechanic will have a lot of different tools at his disposal in order to determine the cause of your Dodge Durango P0456. The most commonly used methods to diagnose this code are:

• The mechanic will usually 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 trouble codes are associated with P0456. 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.
• Following the inspections and repairs, the mechanic will conduct two more tests.
• 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:

The Most Popular P0456 Fixes

Below are the most commonly used Durango P0456 fix:

• Replacing the gas cap
• Replacing EVAP lines
• Replace charcoal canister
• Replacing 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.

You will need to solve the problem quickly. This should help. Please feel free to add anything below.

Are P0456 Serious Concerns?

While P0456 is not going to cause the Durango’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. You should immediately take it in for repair or replacement.

Please leave comments below if you have any suggestions. Thanks!