hey1230000

iTrader: (2)

DTC P0456 - EVAPORATIVE EMISSION CONTROL SYSTEM LEAK DETECTED (VERY SMALL LEAK)

So I was driving to work this morning and all of a sudden, cel came on.. used the accessport and got a p0456 code.. it says symptoms are fuel smell ( I smell this often due to ewg setup ) and a leak less than 0.5mm diameter.. currently the subie is my daily driver and I'm concerned about this.. any help would be appreciated. Thanks!

xhengmanx

iTrader: (57)

gas cap?

Kevoscoob

Most likely gas cap. I had this out of no where and I reseated my gas cap and cleared it and it hasn't come back for months since.

STi-owns-evo

iTrader: (4)

+1 to gas cap. The only other thing I can think of, is if you worked on your fuel pump or something in your gas tank recently, and maybe pinched the gasket on the access panel.

zumnwrx

iTrader: (6)

P0456 is for an "evap system small leak". That means that it is about .02-.1 of an inch that is leaking from. It could be a loose hose clamp, it could be a cracked hose, it could be a valve that is sticky/leaking. There are a couple of vacuum hoses that run into the engine bay, I broke the nipple off of the VSV valve on the intake manifold on my legacy and had a similar code.

unless you have recently done a something fuel related

id start in the engine bay and look over every single boost vacuum hose line connection... pay close attention to the cluster of hoses in the picture and below that area

WRXBOOST10

iTrader: (12)

+1 gas cap first. If not, there's a T fitting near the purge valve that also fails.

hey1230000

iTrader: (2)

I reseated the gas cap, cel still there.. ill check the hoses and t clamp purge valve and the area circled in the engine bay , thanks for the help guys!

kbeetz

iTrader: (3)

That blue T fitting was what caused P0456 for me. Good luck

hey1230000

iTrader: (2)

Where is this t fitting located? I also found a small crack on the power steering pump hose. Not good..

Are you guys talking about the area where the bpv is, near the tmic?

zumnwrx

iTrader: (6)

the T fitting we are talking about is that area underneth what is circled in the picture just check all around those hoses.

sometimes under boost they pop off and it will throw a cell

zumnwrx

iTrader: (6)

here is a pic of the hoses circled in the other pic and how they should be connected

3 hoses connect to the blue T

hey1230000

iTrader: (2)

Alright I will check that area again when I get home, thanks for your help!

hey1230000

iTrader: (2)

So I just took a look down near the area of the t fitting and realized the hose that connect to the t fitting, comes loose fairly easy.. is there suppose to be a small clamp that stays on the T and hose? Would I be able to ziptie it? It's sort of difficult to reach so I would have to remove some parts..

Tried to get a detailed view of the circled area using ALLDATADIY so I can remove some stuff and have a closer look but me being a car Noob, duno any of the name of parts that are within this area.. just replaced the power steering alternator belt and ac belt, and power steering pump hose, got a slight taste in being a car guru, but it was short lived lol

Also, that circle looking thing that connect two hoses , is that the purge control solenoid valve? I have no idea what this does.. lol I've got long ways to go

zumnwrx

iTrader: (6)

i used zip ties on mine...

so was one of those hoses discounted?

hey1230000

iTrader: (2)

It wasn't disconnected, it was all in place but loosely fitted.. with slight movement, it came off very easily that's why I thought maybe some zipties would firmly hold the hose in place.. can the t fitting actually go bad? It's sort of hard to reach down there, not much wiggle room..