Gas smell only when full

So I've noticed this for the past year or so (we dont fill up that often). Whenever our (2010) Gen3 is full, the garage will reek of gas until we've driven it and burned off a couple of gallons. This isnt from spillage at the pump, because if we dont drive the car for a few days, it still smells. It's easily repeatable and always goes away when the gas level drops.

A couple of weeks ago we filled up and had the smell, then over a few days drove it 60mi or so and the smell was gone. Then, in preparation for a weekend trip, we topped it off... sure enough, the gas smell came back. The smell gets into the cabin if we leave it in the garage, but I dont think its coming from inside the cabin. Thats just an effect of being in the garage. We just park it outside and its fine... no smell inside the car.

My theory is that the filler neck needs to be replaced, because the smell goes away after a gallon or 2 of gas is burned away, but I wanted to reach out to the community and see if anyone else has had that problem on a Gen3 (or other car). I obviously could take it to the dealer, but I dont have much faith in my local dealer, and I dont mind working on my car myself.

 

I should clarify, "Top it off" meant fill it up until it automatically stops. I dont mean going beyond when the hose clicks and keep on pumping.

In this particular case, I meant going from 3/4 to full tank as "topping it off"

 

I WISH I'd been rear ended... we've had this mark on the bumper caused by a cyclist leaning against our car and pedaling away (left a big gash) 2 weeks after we got the car years ago. been waiting to replace the bumper cover. where I live the chances of getting rear ended are high. been tapped in most of my cars... somehow this one has lasted a decade without a tap.

I'll check out the evap system. This isn't a particularly new issue and we've filled up at multiple stations over the years so it's not the pump and it's not us going past the limit.

 

Only 2. But it doesnt smell like gas after driving the car for 50mi. Then no more smell for months... it sits in a the garage with occasional use and 0 smell... UNTIL its refilled.

So whatever the problem is, it is dependent on the amount of gas in the tank. If its 3/4 full or less, never smells. Once its full, reeks. Even if left outside for a week, if its full and we put it in the garage, it will smell. Once a few gallons are burned off, we can put it in the garage and it never smells.

 

Fixed - it was a crack in the fuel pump assembly case. Turns out you have to replace the whole thing. Even though the pump/filter/gauge all work. Bummer!

 

yea, I actually was going to play with it, the mechanic had it sitting on the side, but as you can imagine, it reeked of gas. The cracked part was just the upper rim, too.

I decided I would sell the car, but didn't want to sell it smelling like gas. I could have been shady and just had the tank 1/2 full when selling it, but that's not my style.

I was a great car, but we don't need 2 Priuses. We almost always drive the Prime unless we need the capacity (home depot runs).

I did feel like closing out the thread though. I hate when I search the web, find someone with the same problem and then no resolution

 

I bought the Prime because the 2010 was so reliable. Have had that Prime for 2 years (its 4yrs old) and no issues either. Toyota makes great cars