Arione

So for almost 2 years now my 2014 turbo s keeps poping evap leak codes. each time it spends 2-6 weeks at porsche while they "diagnose it" and have consistently been replacing the evap vent tube that keeps rupturing, or the gas cap twice. Every time the leak code pops back up after 100-200 miles, and back it goes. This last time I got it back in December, Haven't even ran a full tank of gas through her and again I get the evap code. the last "fix" was to use a cayenne turbo vent tube apparently recommended by the field tech. Anyone have any idea what's actually causing this? My guess is a valve somewhere either causing a strong vacuum or an over pressurization. One thing to note is last weekend when driving it in sport + and accelerating aggressively it threw a red engine code and reduced the power according to the info cluster, once I turned it off and back on it went away.

huskeric

I would agree with your assertion that the system is being over pressurized. The pressure becomes so great, that something has to fail - and appears the vent line is the weakest link.
Not overly familiar with this particular system, but there is a valve upstream that allows venting back through the TB to the motor for burning/exhaust. Perhaps this valve is bad?
Has this whole line been replaced? Perhaps there is a restriction somewhere is the vent line pathway?

huskeric

Another thought.... to reduce pressure with the gas tank, you may consider filling up at the half way mark or so. The lower the volume of gas in the tank equates to more area for fumes to develop.

huskeric

and lastly, another area to ensure is properly functioning....

https://rennlist.com/forums/panamera...-exploded.html

Arione

Interesting. My dealer has officially given up and has a field tech coming in Feb.

Arione

They finally actually checked the charcoal canister, it was significantly deteriorated. Replaced, lets see if that fixes it

huskeric

They need to be schooled in Occam's razor - simplest explanation having fewest assumptions is usually correct. Considering the charcoal canister is the primary component, one would have thought it would have been the place to start... hmm...

Arione

Yeah, unfortunately I'm in Hawaii. Only one dealer and all the independents have closed / aged out. It was an open secret for awhile that the newer watercooled cars would get subbed out to the dealer from one of the indys anyways because he only knew aircooled cars.