WTF is wrong with my fuel tank/evap?

[DSG2003Mach1]

So a while back my 03 Mach started having fuel pour out the filler neck at the gas cap while fueling when full. The car has no trouble accepting fuel, I put the nozzle in, set the stop on the handle and it'll go until the tank is full. When the nozzle clicks off fuel comes up out of the filler neck and spills down the fender/bumper.

I also start to get a strong fuel smell when it's been running for a while, Im not sure if its possibly related to an evap issue or maybe the car runs a bit rich once its been at temp for a while but I know it's getting hot fuel recirculated to the tank. It is NOT leaking fuel anywhere and the car has no fuel odor in the garage when just sitting there.

The car has a Lethal return setup, it is NOT dead headed. The car ran fine for quite a while (the car has been up and down for several years), the car does sit a LOT. When the Lethal system was installed it got a terminator tank and I replaced the blue-topped evap pieces in the tank with brand new ford replacements.

It is NOT leaking from the grommet where the filler neck goes into the tank.

I have replaced the charcoal canister. I have blown through the valve going to the charcoal canister and it's free flowing in both directions. I blew back through one of the evap lines from the charcoal can to the tank, seems to be free of any clogs. I removed the hard evap lines from the filler neck and don't see any spider webs or anything like that. I did what I could from the bottom side of the filler neck to check for any kind of obstruction.

It started doing this out of the blue and is super annoying. Could it be one of those blue canisters in the tank? How can I check? I just don't know what all this evap crap is to try and figure it out.

@13COBRA - can you run this by one of your techs maybe? I would gladly send pizza and beer money.

 

[13COBRA]

I would bet that the filler neck is out of position, causing it to be able to back up prematurely. We see this a lot, it's not a hard fix once you get to it, but sometimes they can be tricky to detect.

My ACR will do it. Try to turn the gas nozzle upside down while you're filling it. It will cause the fuel to enter the tank just a tad slower, because it's circulating down the neck in a different manor than normal, and I would bet it kicks off like it's supposed to.

 

[DSG2003Mach1]

I would bet that the filler neck is out of position, causing it to be able to back up prematurely. We see this a lot, it's not a hard fix once you get to it, but sometimes they can be tricky to detect.

My ACR will do it. Try to turn the gas nozzle upside down while you're filling it. It will cause the fuel to enter the tank just a tad slower, because it's circulating down the neck in a different manor than normal, and I would bet it kicks off like it's supposed to.

hmmmm, I have had to monkey around down there and theres enough slop thats within the realm of possibility. I'll give that a try, I've tried a few different brand stations and pumps to rule that out.

 

[13COBRA]

hmmmm, I have had to monkey around down there and theres enough slop thats within the realm of possibility. I'll give that a try, I've tried a few different brand stations and pumps to rule that out.

I would almost bet it's the angle. We see this 4 or 5 times a week on various vehicles.

 

[DSG2003Mach1]

I would almost bet it's the angle. We see this 4 or 5 times a week on various vehicles.

well that's interesting to hear, in all my searches I never came across anyone talking about this. I've posted on Modular Fords, NA SVT tech page etc... the only thing anyone ever came back with was checking the evap lines and either the valve on the charcoal can being bad or the charcoal can itself. Then again most of the time you search for any kind of fueling issue it's people complaining about the pump constantly shutting off.

Thanks Nick, the car needs fuel so I'll try it Saturday and report back.

 

[13COBRA]

well that's interesting to hear, in all my searches I never came across anyone talking about this. I've posted on Modular Fords, NA SVT tech page etc... the only thing anyone ever came back with was checking the evap lines and either the valve on the charcoal can being bad or the charcoal can itself. Then again most of the time you search for any kind of fueling issue it's people complaining about the pump constantly shutting off.

Thanks Nick, the car needs fuel so I'll try it Saturday and report back.

Best of luck!

 

[DSG2003Mach1]

Best of luck!

Did not help, actually blew fuel out even further. I'm guessing because of the new edge fender shape the nozzle doesnt end up going as far into the filler neck if you try to turn it upside down. I guess next time I'll just try keeping it half squeezed and see what happens.

 

[THark88]

My 01 Cobra does this as well. I've looked for everything and can't figure it out

 

[WhiteFaleen2001]

Did not help, actually blew fuel out even further. I'm guessing because of the new edge fender shape the nozzle doesnt end up going as far into the filler neck if you try to turn it upside down. I guess next time I'll just try keeping it half squeezed and see what happens.

My car does this. I just keep some paper towels ready (around the nozzle if I am filling up to full on the gas tank). It only shoots out a little bit of gas (I am guessing due to pressure). However, I know for certainty that the anti-siphon nozzle on my filler neck is broken off. I ended up breaking it on accident when switching out the grommet. That is why I believe it is happening to me, since without the anti-siphon valve, fuel would be able to work its way back up the filler neck. I have since purchased a replacement line from a junk yard but haven't installed it yet.

 

[DSG2003Mach1]

When I filled it up this weekend I had the handle half squeezed when I knew it was getting close and it didnt spill. I think Im still leaning towards Nick's comment on it being misaligned from all the times it's been dropped and put back.

 

[NewOrleans-YAT]

I have a raw gas smell from the right rear after running the car. No leaks at all