Gas Tank not filling up

mm3846

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Thanks.
Weird part for me is I have no CELs. Nothing pending either. I’ll try the purge valve and DMTL pump and go from there.

Mine only came up small evap leak. They're both cheap and easy enough to replace to give it a shot.
 

jlglr4

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If the primary symptom is that you can’t refill the fuel tank without the pump trigger cutting you off (i.e., you need to refill very slowly), I believe that’s usually caused by liquid fuel in the canister. Modern tanks vent only into the charcoal canister - they have no other passage to vent vapors. So, if that passage is clogged up (liquid fuel), the air in the tank has no place to go other than out the neck. The pump senses this as a full tank and shuts off.

Faulty purge valve will produce other symptoms, like lean conditions (or a rich conditions if your canister is full of gas), rough idle (if stuck open), pressure/vacuum in the tank, evap codes, etc. Faulty DMTL will generally give you evap codes.

A full charcoal canister can leak fuel also, so filling problems with fuel smell can both be attributed to the canister.

However, if your not having filling problems, and just having a fuel smell, my first thought would be the fuel pump flange on the top of the tank. We’ve seen multiple reports on the forum of these cracking and causing a fuel leak.
 

f1racer328

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If the primary symptom is that you can’t refill the fuel tank without the pump trigger cutting you off (i.e., you need to refill very slowly), I believe that’s usually caused by liquid fuel in the canister. Modern tanks vent only into the charcoal canister - they have no other passage to vent vapors. So, if that passage is clogged up (liquid fuel), the air in the tank has no place to go other than out the neck. The pump senses this as a full tank and shuts off.

Faulty purge valve will produce other symptoms, like lean conditions (or a rich conditions if your canister is full of gas), rough idle (if stuck open), pressure/vacuum in the tank, evap codes, etc. Faulty DMTL will generally give you evap codes.

A full charcoal canister can leak fuel also, so filling problems with fuel smell can both be attributed to the canister.

However, if your not having filling problems, and just having a fuel smell, my first thought would be the fuel pump flange on the top of the tank. We’ve seen multiple reports on the forum of these cracking and causing a fuel leak.
No smell. Only filling problems.
 

ElChuco

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Did you ever find a solution? I'm having the same issue now...

Of course it happened the day I left on a road trip too, and still am not home from it.

I've been able to fill up just fine (very slowly though)

Haven't been home and won't be home for about another month, so I'm just hoping it doesn't get any worse.
My local guy replaced enough parts that the drip which was causing the odor has been resolved. Unfortunately, now my filler tube overflows every single time I fill 'er up. So, I'm going to replace the filler tube, I guess.
 
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