Okay, so I scanned my car for codes, and this is what I got.

PO411- Secondary air Injection system incorrect flow detected

PO420- Catalyst system efficiency below threshold (bank1)

P1456- EVAP Emission control system leak detected (Fuel tank system)

Now the first two codes I got don't really bother me...however the third, P1456 seems like it should be a concern for me. Is this code the reason I smell gas while I'm driving with the window down?

If anybody knows how much these codes will cost to fix, or if I can fixany of them myself?

All help would be greatly appreciated!

 

Is there anything you haven't told us about? Details would have been nice.

Have you have anything done to your intake lately? CAI? Messed around with the airbox? This would be P0411.

Have you done anything to your cat converter lately? Test pipe? Messed with the O2 sensor? This would be P0420.

Have you filled up the gas tank within the last few dozen miles? P1456 is commonly a loose gas cap (not clicked at least 3 times) or a bad EVAP cannister purge valve.

 

The only thing I have done lately is change the air filter, but I replaced it with an oem one.

I have had the engine light on for quite a while but I never got it checked as I assumed it was the o2 sensor only.

I also know that even when I turn the gas cap more than 3 clicks it doesn't get rid of the code.

What I don't understand is the smell of gas I get sometimes when I'm driving and I put the top down or windows down.

I am not the first owner of the car, but as far as I know there are no modifications done to the car.

 

Trace all your vacuum lines. You may have one that has slipped off or has deteriorated at one of the connections. You may also have one of the wiring connections come loose:
https://www.s2ki.com/forums/showthread.php?s=&threadid=105368

You may very well have an O2 sensor gone bad. You must have this checked out. A new one may cost a couple hundred bucks.

The smell of gas could be a bad purge valve. This can be tested. You may also have a bad gas cap. This can be tested. You may also have a bad filler neck. This can be tested. There are fixes for all of these.