getting a p0456 code, what do i do now?

[bluebombersfan]

I looked it up and it says (EVAP emmission control system leak). The question is now what do I do?
Also every time I clear the code it takes about a week of driving for it to go back on. I am assuming this the computer is having r hard time detecting, thus the problem is very minor

 

[97RangerXLT]

what do you do? Find the leak

Check all the lines to the charcoal canister, check the filler neck.

AJ

 

[bluebombersfan]

I suck in this department so I will need some guiding. Basically what your saying is look at all the piping/hosing that connects to the gas tank? This won't be easy for me to find anything I don't think because the leak is very small almost undeductable. I guess I will be looking for any kind of cracks of any sort but it sounds challenging because of the lack of space to really get a good look at everything.
Also how about the senser? could even be the senser going bad too.

 

[Andy D]

Would a loose gas cap be the problem? If your truck is 10 yrs old or older , I would start at the canister up by the battery on my 94 and work your way back down the right side of the engine bay to the right inside of the frame rail. I had to replace and re-connect vapor hoses on mine. But it never lit up a trouble light or ran better. YMMV

 

[97RangerXLT]

what Andy said. if it were a sensor, you would get a specific code for the sensor in question, as the computer would be able to know if it was working or not.

chances are, it is the fuel filler neck, they are a known issue with this truck. 40 bucks on ebay for a replacement.

AJ

 

[adsm08]

Guys, who knows the definition of P0456? Anyone, anyone? Anyone who thinks you are just going to "find the leak"? No one, ok.

P0456- EVAP control leak dected, very small. Can anyone tell me how small "very small" is?

A hole that measures .020 inches across will set this code. You aren't going to just "go find the hole". That is on top of the fact that you have to open up the purge valve and shut down the vent valve, to pressurize the system for a proper test.

The light is taking a week to come back on is because your driving style is not setting the monitor right away, and then other conditions, temp, fuel level, and amount of time the engine is off, all have to be met before it will detect a leak that small and set the code.

You are probably going to need to consult a shop to find this leak. Unless you have a fog machine. If you have access to a fog machine I can work with that.


Personally, I will put money against it being either the gas cap or the filler neck. Those are more likely to set a P0457- gas cap off/loose, or in layman's terms, "screen door on a submarine sized leak".

 

[bluebombersfan]

dam good answer adsm08, This was exactly what I was thinking, how the heck do I find a pinhole leak, your right I won't, and I kind of had a feeling I wouldn't.
I can already assume that this is not a big milage waster by the sounds of it? Question then is how much will a shop ding me to find this needle in a haystack? Can I just tell them I got the code already or r they going to ding me the darn $80 or so bucks just to grab the code again?

 

[TIGGER]

Just curious, did you ever find out what the problem was? I have a buddy at work that just pulled this code on his Mazda pickup.

 

[adsm08]

dam good answer adsm08, This was exactly what I was thinking, how the heck do I find a pinhole leak, your right I won't, and I kind of had a feeling I wouldn't.
I can already assume that this is not a big milage waster by the sounds of it? Question then is how much will a shop ding me to find this needle in a haystack? Can I just tell them I got the code already or r they going to ding me the darn $80 or so bucks just to grab the code again?

If you go anywhere that is any sort of reputable, go in and say "check engine light is on, I want to know what the problem is" pulling the code, doing the smoke test, etc to actually find the problem should all be included in the diag fee. Telling them the code you pulled might help, but they still need to hook up the scanner to do the test correctly.

Just curious, did you ever find out what the problem was? I have a buddy at work that just pulled this code on his Mazda pickup.

His problem might not be the same as your buddy's problem.

 

[Tedybear]

The wife's Tiburon just kicked up a like code. I think it ended in 5. Evap system leak detected....

Turns out those cars suffer from broken hoses, bad purge valves, and the canister can actually dump some of the material in the valve, blocking it open.

It's a wild card trying to figure out these issues. As much as I'm all for DYI?

Dealership Repair. Call and ask first if they have a tech that can use correctly a fog machine to detect evap leaks.

Look at it this way: Trying to do this yourself will take a boatload of time and most likely throwing parts at it. It's easier to have a dealership do the tests---

The dealership also has an added bonus: They have scan tools made for their exact systems. In the case of the Tibby? The dealership scan tool can instruct the ECM to preform special tests that a normal scan tool can't do.

S-

 

[adsm08]

That is the unfortunate part about evap leaks. Of all the CEL diagnostics that could be done on an OBDII vehicle EVAP is about the only one that can only be done by the dealer, with the OEM scanner.