It's too bad the fuel cap will cause a P1456, not the P0411.

P0411 is for incorrect flow of the air injection system.

1st thing is to check all the vacuum lines to the control solenoid, and make sure the solenoid and vacuum tank are not damaged.

 

how can i fix this p0411 code? i mean i know what is it now but what should i do now to fix it? and i do have an short ram intake in my car. thanx

 

is any part of your air injection system disconnected ?. Part of it runs off the stock intake line, if your's is disconnected it would be sucking in unfiltered air, and any vacuum lines/electrical solenoids would trip the code. You have to make sure the system is properly addressed when you switch away from the stock setup.

 

once in a while i get CEL but i didnt want to have to pay 80 bucks for a stupid reading. so first thing, i checked the gas cap, and it was loose, so i cliked it 4-5 times, resetted the ecu, and didnt come back for a while.

I check once in a while to see if the cap is tight or not, and before the light comes on, it always seems tight. but when the light comes on the cap is looose. so i assumed its the cap

 

yeah i checked the gas cap and its really tight and is working like it should. i just dont know what to do to fix the annoying light. i check all the vac hoses and still...

 

I don't know about on 05's, but on my 06 the gas cap didn't throw a CEL it threw a warning message on startup which was fixed in a week of driving cycles.

But google works too, I found this in sub 20 seconds. http://www.honda-tech.com/showthread.php?t=2472262

 

I had the same problem a while back, it was giving me P1456. Now what I do is when i tightening the gas cap I press it against the filler tube kinda hard as I slowly tighten the gas cap, so push on it kinda hard while screwing it on slowly, hope that helps.

 

thanx guys for the help. still have the CEL and i checked every vacuum Hose, and still... im sad with that ugly CEL lol

 

Slow, I know you told me the same thing youre telling this guy...but:

I got the p0411 code, but it went away after I tightened the gas cap properly. Been that way for almost a year, and no signs of it coming back. ::knocks on wood::

 

Turkey tastes good at Thanksgiving too, doesn't mean the 2 DTC's have anything to do with each other.

2 separate emissions control systems. 2 separate monitors that run for each DTC. Tighten the cap all you want. Not going to fix a P0411