Honda Accord P0457: EVAP System – Leak Detected

P0457 This is an example of a common problem code for the Honda Accord. Refers to a code that you receive when your Accord is plugged into a OBDII scanner. The P0457 signifies that the Evaporative Emissions Control (EVAPS) system is leaking. Similar to P0455 for large leaks and P0456 for small leaks, it is also called P0457.

The P0457 issue is not usually a threat to your car's driveability. Certainly anytime the service engine soon light is on though, it’s good to deal with it as soon as possible.

Honda Accord P0457 Definition

The universal OBDII trouble code P0457 can be used to diagnose any problem. It means that no matter what make or model vehicle you have, this code will still mean the exact same thing. Technically, the code stands for:

System 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 leak in the Honda Accord’s EVAP system, it will throw the P0457 OBDII Code.

Honda Accord P0457 OBDII Code Symptoms

A P0457 Code will not usually be associated with other noticeable symptoms. Smells like gas And the service engine soon light.

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

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 operation of your Accord's engine.

Trouble Code Causes of Accord P0457

P0457 can happen for many reasons in Honda Accord. If your Accord 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.

• Evap 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 code P0457. 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 P0457 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 P0457 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.

P0457 Diagnosis- Honda Accord

The mechanic will have a lot of different tools at his disposal in order to determine the cause of your Honda Accord P0457. These are some of the common diagnostics that can be done for the code

• The mechanic will check for other 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.
• Once the mechanic has determined the trouble codes associated with P0457, he or she will usually Take a look at the EVAP system. It includes the purge line, canister, and 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.
• 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:

Most common P0457 fixes

These are some of the more common Accord P0457 fix:

• Replacement of gas cap
• Replacement for EVAP Line
• Replace charcoal canister
• Change 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.

We wish you all the best in finding out why your Honda Accord is throwing the P0457 error code. This should help. Please feel free to add anything below.

Are P0457 Serious Concerns?

While P0457 is not going to cause the Accord’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!