Trouble Filling Gas Tank. Can only fill slowly...

PowrSlave

Member
:
Protege5
I am having a weird issue wherein, once I fill up with about 1.5 gallons, the nozzle disengages and thinks the car is full. Depressing the lever again only causes it to disengage immediately and only puts a few drops in each time. However, if I put gas in slowly, it will fill up.

I tried taking some of the hoses off around the one way vent valve and blew compressed air through them, but it didn't help. I also blew some compressed air through the one way valve (not against the valve, for risk of damaging it). I can't seem to find an obstruction and the vent tubing doesn't appear to be damaged or kinked. I can't seem to determine how to blow air through the actual vent hose that goes to the filler cap area since air doesn't seem to come out the tiny hole at the top when I do experiment with blowing air up from the bottom.

Does anyone have any ideas that might be particular to our P5s that might help me to solve this?
 

pcb

The Diagram Dude
:
2002 MP5
Check all the components circled in red for blockage or being filled with gas.

Apparently if you fill up the gas tank too much, gas can flow backwards down the vent tube and fill up the cylindrical canister preventing it from venting.

Fuelvent_zps52a2a932.jpg
 

Brian_K

Member
:
Protege5
That black filter canister pcb circled above is clogged with fuel. Just remove it and you'll be able to fill up gas normally again
 

PowrSlave

Member
:
Protege5
Ok, so I disconnected the charcoal cannister to see if I could fill the car up properly and I had no problems, so I imagine that there is an issue with the cannister. I noticed some gas came spilling out one of the hoses that I disconnected from the cannister. I only expected vapor to come out, so that was somewhat surprising. Does gas normally flow through the cannister like this? I thought a gas soaked cannister was bad.

Regards,
Zach
 

kms1990

Member
:
2011 mazda 3 hatchback GT
that gas soaked canister sounds like your issue to me. it cannot vent correctly and so shuts off on you. this is caused by overfilling too much too often
 

PowrSlave

Member
:
Protege5
I only fill my tank when 1/4 remains. I've never topped off. My concern is that if I replace the canister that the new one will also get soaked since gas leaked out of one of the disconnected hoses when I was attempting to fill it without the current canister hooked up. But if the consensus is that the canister is the problem, I guess I will have to try replacing it and see if the new one lasts.
 

PowrSlave

Member
:
Protege5
Ok, so I replaced the canister and that allowed me to fill the tank up to 3/4 full, but it stopped at that. I figured that was an improvement, but the next time I filled up from 1/4 full the problem returned and I still have to fill it super slowly. So the problem must be something other than that canister. Frustrating.
 

Marchy

Member
:
2003 P5, 2013 BRZ
I have the same issue in my wifes P5, curious to see if you find anything else that might be the cause.
 
:
97camaroSS e30 318is Spicy #1348
Anyone have the part number for that evap canister located in the back drivers side wheel well?
 

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