Lincoln Town Car P0456: EVAP System – Small Leak

The most frequent trouble code with the Lincoln Town Car Is the Code P0456. This is the trouble code that you get when you plug in your Town Car to an a OBDII scanner. The code P0456 indicates that the evaporative emissions control system has a tiny leak. This code is often found with or related to P0440, P0441 and P0440.

Normally, P0456 does not pose a danger to the Town Car's ability to drive. 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 Lincoln Town Car, it is actually referring to the amount of pressure lost, and not the physical size of the leak. They can also be very minor.

Lincoln Town Car Definition P0456

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. The code is technically:

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 to start the normal combustion process. When there is a small leak in the Lincoln Town Car’s EVAP system, it will throw the P0456 OBDII Code. If there is a large leak, it’ll throw P0455.

Lincoln Town Car OBDII Symptoms P0456

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 Town Car's engine.

Trouble code for the Town Car P0456

P0456 can be triggered by many factors in Lincoln Town Cars. If your Town Car 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.

Below are the top most probable problems that could throw the code. These were listed alphabetically, in some order.

• 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 code P0456. 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. You will need to locate and take out a few clips.
• 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.

P0456 Diagnoses- Lincoln Town Car

The mechanic will have a lot of different tools at his disposal in order to determine the cause of your Lincoln Town Car P0456. These are some of the common diagnostics that can be done for the code

• The mechanic will usually check for any additional trouble codes. A mechanic will usually check for additional trouble codes to help diagnose the problem. 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. Check out the EVAP System. These include the line and purge valve.
• A mechanic will examine the gas cap and verify that it is able to withstand high pressure. 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:

The Most Popular P0456 Fixes

Below are the top-rated Town Car P0456 fix:

• Replacing the 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.

We wish you all the best in finding out why Lincoln Town Cars are throwing the code P0456. This should help. Please feel free to add anything below.

Do you consider P0456 to be a serious concern?

While P0456 is not going to cause the Town Car’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!