So I have been reading a ton about the P1457 code on this forum and others. My CEL was on for about a week and then went off a day after I filled my tank up with fuel. I don't completely understand how the EVAP system works but could this code have been from bad fuel or is it more likely that it went off because there is more fuel and therefore less vapor in the system?

 

the last time you filled up you prob didnt tighten the gas cap all the way ..which would cause an evap code..

 

This code indicates EVAP leakage on the canister side (not the fuel tank side) and isn't typically triggered by a loose fuel cap. Loose fuel cap typically gives a P1456 code.

Just to be safe though, a week earlier I replaced the fuel cap, reset the ECU and the light came back on in a day. So, I don't think it had anything to do with the cap in this case.

 

Read this: https://honda-tech.com/forums/honda-civic-2001-2005-78/faqs-guidelines-read-before-posting-2101211/

Search before making a new thread. (some results for P1457)
https://honda-tech.com/forums/honda-civic-2001-2005-78/p1457-code-02-civic-2065407/
https://honda-tech.com/forums/honda-civic-2001-2005-78/cel-%7E-help-me-out-2476095/
https://honda-tech.com/forums/honda-civic-2001-2005-78/check-engine-light-gas-cap-problem-1826277/
https://honda-tech.com/forums/honda-civic-2001-2005-78/cel-code-20-a-1767877/

 

Thanks for the links. I read all of these before I posted this and even posted on one of them. I am asking a specific question that hasn't been covered on any of the other threads.

 

inspect the canister itself for cracks and the hoses leading up to it. Ive never been able to fully diagnose this problem without using a smoke machine or vacuum hand pump. Last time i saw this problem, a solenoid was stuck open, causing the EVAP to constantly vent.