Planet-9 Porsche Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
81 Posts
Discussion Starter #1
Just got this tday,no running problems, cars running great.
No smell of gas,Tank was at 1/4 full. Filled it and took fuel ok.
Code # P0455 Large Evap Leak
Any idea what or were to find problem. Thx
 

·
Premium Member
Joined
·
1,600 Posts
If that doesn't work it's a crack probably in plastic of the emission evaporation system
Had same code in my BS 04. Part (vent line) wasn't that much $286 (overnight shipped) but labor $562 was a lot as you have to take the front trunk apart to get to it.
You do a smoke test to find where the leak is.
 

·
Registered
Joined
·
81 Posts
Discussion Starter #4
Thx guys, I turned off the check engine light and it has not come on since but ive only driven it maybe 50 miles.
I called my INDY and he said it will most likely come on when fuel drops to 3/4 or less. I have an Appt on June 9
to have it smoked if needed. Hopefully its a minor problem. Its definitely not the fuel cap.Cap and seal r perfect and this code is for a Large leak. With no smell, and no issues feeling Indy said its most likely the sticky or broken
vent valve into the Tank,theres 2 apparently.
 

·
Registered
Joined
·
969 Posts
On my Boxster, and my current Cayman it was the evap canister, leak detection pump that needed to be replaced. The code came up as I would start the car.
 

·
Registered
Joined
·
81 Posts
Discussion Starter #6
Update: Pulled the seal out on my gas cap which visually looked ok when it was installed BUT far from it
when pulled out.Big cracks all the way around. I have installed a seal that I have from another cap which looks
identical and is in perfect shape. Im not sure if that would prompt a LARGE vac leak. Thought it would be a small
leak with a different code, regardless the light has stayed of from full tank to 1/2 tank.Will run the tank down to 1/4 were it came on previously.Maybe I will get lucky!
 

·
Registered
'07 Cayman 'S'
Joined
·
55 Posts
I had the same issue on one of my Toyota trucks a couple weeks ago. 'Check engine' light illuminated and there was a ignition miss feeling at idle, but it wasn't affecting the fuel economy. A quick look under the hood found a hose disconnected from a charcoal vacuum unit of some sort. Snipped off the cracked end of that hose and reconnected it - then cleared the code. Idle returned to normal and it appears that corrected the problem.

I'd look for disconnected and/or cracked ends on all your vacuum hoses. Usually there's enough length to snip 1/4" or so off the ends to get past the cracks. Good for at least another few year or so.
 
1 - 7 of 7 Posts
Top