Dodge Caliber P0456: EVAP System – Small Leak

The most frequent trouble code with the Dodge Caliber The Code P0456. This is the trouble code that you get when you plug in your Caliber to an OBDII scanner. A P0456 code indicates that there may be a slight leakage in the evaporative exhaust control system. This code is often found with or related to P0420,P0441 and, very rarely, P0440.

The P0456 issue is not usually a threat to your Caliber'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 Caliber, it is actually referring to the amount of pressure lost, and not the physical size of the leak. This can happen in very small amounts.

Dodge Caliber P0456 Definition

The universal OBDII code P0456 can be used to diagnose trouble codes. The code can be used regardless of the make and model of the vehicle. Technically, the code stands for:

System Leakage of Small Size – Evaporative Emission System

The EVAP system collects fuel vapor from fuel tanks and then sends it to the intake to ignite the engine in normal combustion. When there is a small leak in the Dodge Caliber’s EVAP system, it will throw the P0456 OBDII Code. If there is a large leak, it’ll throw P0455.

Dodge Caliber P0456 OBDII Symptoms

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

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

Caliber P0456 Trouble code Causes

The P0456 trouble code can be triggered by many factors in Dodge Caliber. If your Caliber 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 main problem that can cause the 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. You may not get the message but a P0456. 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. 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.

Diagnosis for Dodge Caliber P0456

To diagnose the problem with your Dodge Caliber's P0456, a mechanic can use a variety of tools. These are some of the common diagnostics that can be done for the code

• Check with the mechanic to determine if any additional trouble codes are present. 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 P0456, he or she will usually Check out the EVAP System. These include the line and purge valve.
• 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:

Most common P0456 fixes

Below are the most commonly used Caliber P0456 solutions:

• Replacement of gas cap
• Replacing EVAP lines
• 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 check your gas cap.

You will need to find the cause of your Dodge Caliber throwing the P0456 code. This should help. You can add any additional information by leaving a comment.

Do you consider P0456 to be a serious concern?

While P0456 is not going to cause the Caliber’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.

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