Kia Rio P0457: EVAP System – Leak Detected

P0457 It is quite common to encounter the trouble code Kia Rio. This is a reference to the number you receive when your Rio plugs into a OBDII scanner. The P0457 signifies that the Evaporative Emissions Control (EVAPS) system is leaking. This is similar to P0455, which indicates a large leak, and P0456 that indicate a small leak.

Normally, P0457 does not pose a danger to your Rio's ability to drive. Certainly anytime the service engine soon light is on though, it’s good to deal with it as soon as possible.

Kia Rio P0457 Definition

The universal OBDII trouble code P0457 can be used to diagnose any problem. The code can be used regardless of the make and model of the vehicle. Technically, the code stands for:

System Leak – Evaporative Emission System

The EVAP system collects fuel vapor from fuel tanks and then sends it to the intake of the engine to ignite the regular combustion process. When there is a leak in the Kia Rio’s EVAP system, it will throw the P0457 OBDII Code.

Kia Rio P0457 OBDII Code Symptoms

The P0457 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 smell of fuel near the fuel tank or fuel filler tube.

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 engine.

Rio P0457 Trouble Code Causes

Many things can trigger the P0457 code in your Kia Rio. If your Rio 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.

• 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. It should have a tear or a hole. 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. It can lower the tank pressure, which could throw out 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 P0457. 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.

P0457 Diagnosis Kia Rio

To diagnose the problem with your Kia Rio's P0457, 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 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.
• Once the mechanic has determined the trouble codes associated with P0457, he or she will usually Check out 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:

The Most Popular P0457 Fixes

These are some of the most popular Rio P0457 fix:

• Replacement of 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 check your gas cap.

You will need to find the root cause of your Kia Rio throwing the code P0457. This is our hope. You can add any additional information by leaving a comment.

Are P0457 Serious Concerns?

While P0457 is not going to cause the Rio’s engine to stop running, it should not be treated lightly. There could be fuel contamination. Check your fuel level to make sure it is not leaked. You should immediately take it in for repair or replacement.

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