2008 honda civic-lx --check fuel cap error---

Hi bought a new 208 honda civic in November, recently I got a check fuel cap error, of course I did and its fine. Then the check engine light came on so i went to the dealership. The error code indicated a vapor leak, but they could not find one and reset it. Then a few day later I get the check fuel cap error and then the check engine light. So I again return to the dealership, again the error code says “SMALL EVAP LEAK DETECTED” and they ordered parts i.e. EVAP CONTROL CANISTER, so I returned to have them install this and the test indicated it was all normal. So I then go along and you guessed it this weekend I get the check fuel cap error and then the check engine light. So now I am back having to go to the dealership, it is a pain in the behind for sure. I note that it seems to happen about 2 days after I have filled up the car and I always check the gas cap to see if its on properly, any one have any suggestions??

I have two suggestions:

*Stop pumping gas as soon as the pump clicks off, and DO NOT attempt to force more gas into the tank. If you have been forcing extra gas into the tank, you may have already damaged the evaporative emissions canister and/or valve.

*Start reading the details of the “Lemon Law” for your state. In most states, the dealership gets only three tries at remediating a specific problem. But, if the owner is not aware of the statute’s details, he may not avail himself of coverage.

Hi, I always stop filling the car when the pump stops and never top off. Plus I find it strange that I have had the car since NOV 17th 2007 and its only now doing this. I bought the car in NC and just moved to Houston TX, so not sure if that will affect the lemon law stuff, I have just made an appointment at the dealership for tmrw, including tmrw I have been in there once a week for the past 3 weeks! So will see what they say this time.

I agree 100% with VDCdriver about not topping off your tank when filling it up. It can do some expensive damage to the vapor recovery system.

You have not said if you have replaced the cap. If not I suggest you start there. Be sure to get the right one. It may not fix it, but it is cheaper than most anything else and it is worth trying.

I also suggest that any time someone reads the code(s) on your car that you write down the actual number. It will be in the form P0123. Then post that number here.

Hi, I havent replaced the fuel cap and do not know if the dealership has done this or not. The error code both times has been P0456. The parts they replaced were: Valve Assy and Canister Assy. I am assuming it will be the same error code when I go back tmrw.

The most common reason for this code is the failure of the car owner to screw on the fuel cap until it “clicks” at least three times. If you are not already doing this then try it and you will likely find your problem going away.

If you are already making sure that the fuel cap is clicking three times every time you fill up then there is something wrong and the dealer needs to trouble shoot it for you.

Good luck.

So I got back from the dealership and they said they contacted HONDA TECH and they said that the Valve Assy and Canister Assy they has installed was faulty. Apparently there is a faulty batch, so now I have to wait for the new parts and go back again for it to be installed. So we shall see what happens after that, I am dubious on this is the issue so will wait and see.

had the same thing happen to me. while i was at autozone getting the code some kid overheard what had happen and told me to go and take off the gas cap and put some lube on the seal. went home with codes & tried what he said . the next day driving down the expressway the light went out. don"t know if whether it was the reason or not??? so far so good good luck

Have you tried replacing the fuel cap? You can either buy one at the dealer or you can save a few bucks by buying one at an auto parts store. Either way it might solve your problem.

Even though the gas filler cap is often the cause of a leak in the Evaporative Emissions System leak, it’s not always the cap. The Trouble Code of P0456 is for “Evap. Emiss. Sys. Leak Detected (very small leak)”. Whereas, P0457 is for “(fuel cap loose/off)”, which hasn’t been displayed. Since it’s a “very small leak”, it could be very difficult to find the leak. I think the standard of a pin-hole (equivalent) of 0.020" (20 thousandths) is too rigorous, and unrealistically small. Unfortunately, it’s the “law”.