EVAP – P0497 problem

[TheZipWad]

So for about a year I’ve had this P0497 problem come and go on my 2004 Honda Civic LX Sedan. At first I put some Gumout in my gas tank and it went away. Then later it came back and people told me it was probably the gas cap. I bought a new Honda gas cap and it went away again but came back a few months later. I put more Gumout in and it went away again for a few months and now it has come back again. I tried Gumout again but now it’s not going away and I still have the P0497 – “EVAP system low purge flow”. I took it to a shop and the first thing they said is that it was the gas cap and tried to sell me a new gas cap. Even though my current gas cap is less than 6 months old? =(

I tried to go to the dealer but they said it would be $200 just to determine what the problem is. So I guess I’m leaving that as a last resort. Anyone have any ideas?

Topic

[pcmdjason]

Take a look at these videos for more information on where the problem could be.

How the EVAP system works and what causes codes:

http://www.youtube.com/watch?v=Dfj-F_pTj5M

How to diagnose EVAP problems:

http://www.youtube.com/watch?v=CSn0ljUS … ure=relmfu

Another video on EVAP testing:

http://www.youtube.com/watch?v=RwFCqu5s … re=related

[EricTheCarGuy]

Yea that shop was WAY off in their diagnosis. In order to find evap problems you normally need a smoke machine and the ability to activate the diffrent components of the system however in your case it sounds like you have an issue with purge flow do I might start by checking the lines from the purge control solinoid to the canister to see if there are any problems there. I know this sounds weird but also check the vent tube on the bottom of the canister for spider webs and if you find them remove them as any restrictions here can cause purge flow problems. There was actually a TSB on this a few years back.

[Author]

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