Code P0457, “Check fuel fill inlet” message turned on?

LETHAL2LOVE

MEMBER
2013 LINCOLN MKX
4WD
AUTOMATIC
165,000 MILES

A couple months ago I got a notification to “check fuel fill inlet” as it is a capless tank. I did some research and purchased some carb cleaner and cleaned the fuel fill inlet as best I could. This cleared the notification for about 2 weeks. At random without reason, it reappeared, And I left it alone for about a month. Last night on my way home from work my check engine light came on (no it’s not flashing) and my car started driving differently. It was consuming a lot of gas and almost seemed like it was struggling to accelerate or go uphill. It was louder than normal during acceleration as well. Today on my way to work it was still driving irregularly, I was gentle with it even though it hadn’t done anything severely alarming yet. I stopped at O'Reilly's and had the Veri scan device connected to read the code. It gave me a P0457 -EVAP system leak detected (fuel cap loose / off) -, and told me that my emissions status was Red due to the issue. My confusion within that is that there ISN’T a fuel cap, it’s an EZ fill inlet. So, on my break from work I used the carb cleaner again just as I did before but this time it didn’t clear the notification from my warnings. Please help. I love my car, and I just want it to work like it was before this dumb problem.

Thursday, September 5th, 2024 AT 3:12 AM

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
50,622 POSTS

So, with the code P0457 and the gas cap problem the system assumes there is a leak, but the leak can be anywhere in the EVAP system.

This guide can help with the problem:

https://www.2carpros.com/articles/evap-system-code-repair

I would use a flashlight and check the EVAP lines to make sure none have fallen off or are cracked or damaged. Also, I have seen the EVAP purge valve stick on which can cause the light and the engine low power problem as well. Here is the location of the purge valve which I would remove and see if you can blow air through it and if so, the valve is bad. I also included the EVAP canister hoses and location so you can check it out.

They did have problem with the Non cap style of gas fill which will need to be replaced if leaking. To tell if it is leaking you can remove it to see if you can blow air through it as well.

Check out the images (below). Please upload pictures or videos in your response of any problems so we can see what to help you with.

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