I just jumped my OBDII to try and pull the code, but it kept flashing patterns of 9 "long lights" over and over. 9999? or 99? It didn't make sense to me. I went to Autozone and they pulled P1457 or P1456, I forget which one, whatever one could be the fuel cap. So I was like oh, ok, so I tightened again and reset the ECU and everything, and then drove for 2 hours the following day with no problem. Then the morning after that on my way to work the CEL came on again. Could it have really taken 2 days for the same troube code to reappear? I'm thinking that it wasn't my fuel cap in the first place, and now it's some bigger problem.

But the flashing lights I got don't even match up to a code! I would appreciate some help, quickly, because I have to deal with this today. I leave for vacation tomorrow, but need my car when I get back. I'll be waiting! thanks

 

[align=center]P1456[/align]EVAP Emission Control System Leak Detected (Fuel Tank System)

That should be the gas cap issue.... does your cap have a missing or bad o-ring on it?

 

No, the seal seems perfect. I even opened it up once the car was running and I got a big suction sound, so I'm pretty confident everything is sealed properly. Can you confirm that the other parts it could possibly be are EVAP canisters or something like that? They said if not the gas cap, some kind of canisters I've never heard of. The parts themselves cost 85 each at autozone, I'm sure way more at my dealer.

 

Get the number.

P1456 = EVAP leak in the tank & related stuff.
P1457 = EVAP leak in the canister& related stuff.

I had AZ read P1457 but they told me it was the gas cap. So they're kinda creative with their explanations. You need the number.

If it's P1456, the cap is the most likely thing. But there's like 8 or 10 other things that can possibly cause it, and you've already ruled out the cap. Also, P1457 has 1 or 2 things that are most likely, but 10 or so that are also possible.

Here's a thread,& there's probably more if you search for "P1457"
https://www.hondaaccordforum.com/m_52038/tm.htm

 

Is the gas cap tight 3 clicks or more? Does it tighten smoothly or does it bind slightly?

 

Yes, the cap it tightened even more than three clicks, but the hwole thing seems smooth and I've looked at it carefully and should be completely fine. It was P1457. And I think at this point that I will take it to the dealership, so it can be fixed for sure. I just have to also remember to bring the KY with me too...[:'(]
Thanks for the help everyone.

 

A gas cap wont cause that code. The first thing I would check is the canister vent shut valve if you live in an area that uses salt on the roads.