I"ve replaced the gas cap on my 1999 honda accord v6, the check engine light is still on, is there some kind of filter for the excess gas emissions under the car some where or the engine compartment that I could replace?
Thanks for your help.

 

What I would do is take it to an Autozone and have them pull codes to let you know what the problem is or if you are sure that cap was the problem,disconnect the battery cable for 10 to 15 seconds and then re hook it and that will reset the computer.Good luck Bobby.

 

I had the same issue with my 99 Civic LX; The Actron pulled the P1456 code which is a small EVAP leak. I replaced the gas cap and cleared the code. I drove it around for a month or so, then the same CEL and code came back. The first thing i did was check/listen to ensure my gas tank was pressurized. If you take the gas cap off and notice a hissing/venting sound then its not the gas cap. Check your EVAP Canister/ and hoses.