Fuel leaking from charcoal cannister drain hose (FD)
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Joined: Jan 2016
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From: Melbourne, Australia
Fuel leaking from charcoal cannister drain hose (FD)
I have a Series 8 Type RS and am trying to understand a potential issues I noticed at a track day recently.
In my car I have retained the charcoal canister but unplugged the hose (out of the charcoal canister) that would eventually go to the purge solenoid (and removed the purge solenoid). From my understanding, this setup would allow the car to continuously vent fuel vapor into the air with the canister slowing the rate of dissipation.
What I did notice at the track (during a pretty hot day) was a strong fuel smell coming from under the car. I jacked it up and noticed that the drain hose (at the bottom of the canister) was actually wet as if it had been leaking fuel.
1. Is this something to be concerned about?
2. Would it be better removing the charcoal cannister completely and just venting to atmosphere from after the two check valves? Or worth keeping the canister connected?
While probably irrelevant, it may bear noting that I got some pretty severe fuel surge at the tank with fuel pressure dropping over 50kPa below target while coming onto boost out of a corner.
In my car I have retained the charcoal canister but unplugged the hose (out of the charcoal canister) that would eventually go to the purge solenoid (and removed the purge solenoid). From my understanding, this setup would allow the car to continuously vent fuel vapor into the air with the canister slowing the rate of dissipation.
What I did notice at the track (during a pretty hot day) was a strong fuel smell coming from under the car. I jacked it up and noticed that the drain hose (at the bottom of the canister) was actually wet as if it had been leaking fuel.
1. Is this something to be concerned about?
2. Would it be better removing the charcoal cannister completely and just venting to atmosphere from after the two check valves? Or worth keeping the canister connected?
While probably irrelevant, it may bear noting that I got some pretty severe fuel surge at the tank with fuel pressure dropping over 50kPa below target while coming onto boost out of a corner.
In general it's possible for raw fuel to make its way to the charcoal canister. People who try to squeeze as much gas into their fuel tank as possible, sometimes push fuel past the tank into the canister. I don't think that its out of the question during heavy cornering with a full tank of gas, that some can make its way down the line.
If you are not worry about passing emissions, then you can just get rid of the canister, otherwise when the system runs an EVAP test it'll fail and throw a code for a large leak.
If you are not worry about passing emissions, then you can just get rid of the canister, otherwise when the system runs an EVAP test it'll fail and throw a code for a large leak.
Thread Starter
Full Member
Joined: Jan 2016
Posts: 54
Likes: 6
From: Melbourne, Australia
Makes sense. I only noticed it while the fuel tank was getting low, but it's possible it splashed up there earlier in the day and took some time to make its way through all the charcoal.
On a Haltech Elite, so no issue with codes. I could set up the EVAP system but digital outputs are in short supply, so would rather use that for something else.
So there's really no benefit in running the charcoal cannister without the rest of the EVAP system then? I guess if it's filling up with fuel, it's just a potential fire hazard.
On a Haltech Elite, so no issue with codes. I could set up the EVAP system but digital outputs are in short supply, so would rather use that for something else.
So there's really no benefit in running the charcoal cannister without the rest of the EVAP system then? I guess if it's filling up with fuel, it's just a potential fire hazard.