What would cause pump to kick off all the time when filling gas tank?

Unfortunately there is probably not much you can do with this one. Cars that usually suffer with this kind of problem is mainly down to the design angle of the fuel filler neck. The flow rate of fuel does not drain quick enough and thus you get the block off issue at the pump. Try inserting the nozzle at half engagement into the cars filler neck and try keeping the angle of the hand pump at a less acute angle (keep the nozzle at a horizontal angle). This should help ease the flow into the fuel tank.Try it and please let me know if this has helped. Pani

we had the same problem with a Subaru. They replaced some sort of valve in there and it's fixed.

you may have faulty evap vent control valve. it opens to allow fuel to enter the tank and closes to pressurize your fuel/emissions control system these are common Nissan problems. I dont have a Toyota background so i cant say for sure. If this is your issue expect to pay 3 to 400 parts and labor depending on your area. I hope this helps you do not take this to a Joe Shmo garage this is a dealer issue. Mike - nissan asst service manager.