Evap canister full of water

[FowVay]

For discussion, what do you think would cause my evaporative emissions canister to fill with water? At approx. 37,000 miles my 2017 Nissan Frontier w/2.5 liter engine started having difficulty taking on fuel. This weekend I had the opportunity to investigate the issue and found that my charcoal canister was full of water.

I removed all of the vapor lines and ensured they were clear and I inspected everything to verify that no cracks or leaks existed in the system. The only line I found with moisture was the canister vent line which vents to atmosphere and is controlled by the vapor vent solenoid. The vapor vent control solenoid and the pressure sensor both worked as designed and I had no DTCs or CELs related to this situation.

The only thing I found out of the ordinary is the vent line with the moisture in it. This line vents to the fuel filler neck (on the outside - not internally) and is open to atmosphere exactly where the fuel cap threads on. There is a seal that seals the fuel filler neck and it wasn't seated. I didn't pay enough attention during removal to notice whether the tiny drain hole in the seal was at the bottom where it is supposed to be. There is no splash shield around the filler pipe to keep water from spraying on the filler neck or vent line and we had an unusually wet December so this may be the problem.

Has anyone else had such an issue with water in their charcoal canister? I did drain the water and purged the canister with compressed air to dry it out. The service manual states that if the canister weighs over 2 Kg (4.4 lbs) to replace it. Mine weighed nearly 6 lbs before I dried it.

 

[demarpaint]

Subscribed. I was having fueling issues with my Liberty, and it seems to have fixed itself, for now. I'll leave it at that, not to hi-jack your thread.

 

[Linctex]

Drain it the best you can, then place it in the oven at 225*F overnight.

I agree - it's weird that it happened.

 

[Anduril]

I know in the XTerra, the canister would fill with dirt over time if you off-roaded it without re-routing the fresh air hose and adding a breather filter. The outlet for it was inside of one of the frame rails. I wonder if water could get in the same way?

 

[dishdude]

Wouldn't this be covered under the emissions warranty? Are you sure it's water and not fuel?

 

[FowVay]

Water ingression is not a warrantable issue. This is simply a design flaw. Nissan issued a TSB on August 16, 2018, to address blockage in the vapor vent lines but that is not the case here. I tested all ventilation circuits with a smoke machine and had no blockage.

The fluid in the charcoal canister was water. I am going to design a line filter and shield to put on the vent line to keep water away from the opening. As Anduril stated, this has been an issue with Nissan trucks for a very long time. The TSB applies to Frontier trucks back to 2005 and even to the 350Z back to 2003.

 

[LeakySeals]

I own a Nissan, so I'm not surprised by weird problems. Move the end of the vent somewhere else so its not sucking water. Or somehow shield it.

 

[FowVay]

Thanks for the input guys. I'm going to try to shield the vent hose and see if that resolves this problem.

 

[Anduril]

I extended mine and ran it up behind the driver's side tail light. There's enough room for a breather filter in there.

 

[FowVay]

What sort of breather filter did you use? Was it an OEM Nissan? If so, what is the part number? Thanks,

 

[Anduril]

Just something from eBay. I routed the evap line behind one tail light and put a filter on it, and I routed the axle vent behind the other one and also put a filter on it. I don't know if they updated the design on later trucks but on my 2005, the axle vent is just sitting there where it will either get caked in dirt/mud, plug up, and blow a seal, or take on water if you drive through something deep enough. There's an adapter you can buy (actually has a Nissan part number) that screws in in place of the stock vent and will fit a 3/16" inside diameter hose to route wherever you see fit.

 

[Happycamper]

I own a 2017 Frontier. The first time my emission light went on was around 12k miles in Dec 2018. It was nearly impossible to put gas in it. When I had the codes pulled, it showed a code of po448.
The dealer replaced the canister, solenoid, and neck. The canister was full of water.
All was well until 2/15/19 when the light went on again. The same code appeared.
When I called the service manager, he genuinely was shocked. I asked him if this code has been a problem with the frontiers.
He told me that Nissan sent out a memo on 2/4/2019 that this is indeed a problem and there are SEVERAL parts that need replaced plus they are going to cover the canister.
Just thought I'd share.

 

[Happycamper]

I own a 2017 Frontier. The first time my emission light went on was around 12k miles in Dec 2018. It was nearly impossible to put gas in it. When I had the codes pulled, it showed a code of po448.
The dealer replaced the canister, solenoid, and neck. The canister was full of water.
All was well until 2/15/19 when the light went on again. The same code appeared.
When I called the service manager, he genuinely was shocked. I asked him if this code has been a problem with the frontiers.
He told me that Nissan sent out a memo on 2/4/2019 that this is indeed a problem and there are SEVERAL parts that need replaced plus they are going to insulate the canister.

 

[FowVay]

Thanks for the info Happycamper. I'm at 40,000 miles and out of the warranty and since I never had any CEL or emissions related fault codes it was just something I resolved myself.

i drained the canister and dried it and I also made a splash shield to protect the vent tube from water spray. Why they don't use fender liners anymore is a mystery but that would have prevented this whole problem.

I'm quite disappointed with Nissan and their offerings. Thankfully this problems hasn't cost me any money to fix.

 

[cronk]

Is this truck short tripped a lot by any chance?
Typically, the charcoal canister is designed to absorb fuel vapors, the under certain conditions, typically highway driving, the purge solenoid opens and allows the fuel vapor to be drawn out and burned in the engine .
Wondering if it is short tripped most of the time, might not allow the purge cycle to run.
Evap systems seem to be a thorn in the side of many oems, I know gm had a similar issue a decade ago on silverado pickups and issued a tsb to add a remote filter and hose to prevent the vent valve from allowing dirt and moisture in, sounds like this would help your truck.

 

[FowVay]

Cronk, the truck averages 20,000 miles per year so it's definitely not a short tripper.

The vent solenoid is closed and vents fuel vapors to the intake manifold during open throttle situations. When the vehicle is in deceleration mode or idle mode the vent solenoid opens and vents to atmosphere. The way the vent tube is routed allows water to spray from the road onto the tube and during times of very wet operation this can allow water to get into the vent tube and ultimately into the canister.

My canister filled with water during a time that we had nearly a full month of heavy rain in my area - Nov/Dec 2018. The vent tube leaves the canister and travels up the fuel filler neck and is open to atmosphere at the fuel cap. There is a foam seal around the fuel filler neck and this is where the water was getting into the vent tube. I sealed the area around the foam and have not had any issues since. Of course, we haven't had nearly as much rain either. I am hoping this resolved the issue permanently.