I had a bad fuel pump a while back and I replaced it with an assembly I found on rock auto ( brand was auto best I think and it was cheaper but listed as best seller).
However, ever since then, when I fill up, the pump will shut off like the gas tank is full, but it's not because I'm empty and only put in a gallon. It does this multiple times per fill up and I have to hold the handle in a way to make the gas pump very slow.
It's more of an inconvenience but I do want to know why it's doing it. I know there's a vent tube or something next to the fill up hose but that seems clear. Can the type of fuel pump assembly cause this? Did I get a shitty brand?

 

My first thought would be that your filler neck is bent, crimped, or twisted in a way that is A. causing fuel to pool inside the neck or B. blocking the air intake hole of the stations nozzle. In either case this would cause the nozzle to shut off. I can't see a way the fuel pump itself would cause the issue, most likely just something slightly off due to disconnecting the neck.

 

Okay I'll look at it tomorrow or Friday. I did blow in the vent tube and I had a partner listen and they could hear the air coming out, so I'll test our the filler tube theory!

 

It is the filler hose or vent hose, for sure.

No, fuel pump can't cause this

When you pump gas into the tank the exact same amount of air must come out, if it can't get out then gas backs up in filler tube and pump clicks off.

Or if gas can't flow into the tank as fast as pump delivers it then it backs up and pump shuts off.

Air and gas can flow because you can put gas in, so its not BLOCKED, but not enough air or gas can flow which is why it clicks off

Those are the only two reasons for your symptoms

 

Thanks, guys!

 

I was doing my brakes and wheel bearings today and thought I'd take a look at the filler tube and see if I could see anything visibly wrong with it but nothing caught my eye. I followed the hose with my hand until it met the tank and I didn't feel any bends are kinks.
i attached some pictures of both the hose and the opening in case that would help. Thanks!