[bizzleb109]

I have a 2007 335i been over filling petrol and now my fuel gauge is always showing near full. A few days ago my car powered off called rac and it was due to no fuel. So I put in 20.00 after 40 miles put another 30.00 drove about 60 miles and then decided to fill up tank and it only took 42.00 full tank. I've been told the float is probably stuck. Any how if float is stuck I filled up it only took 42.00 for full tank. Due to float stuck would petrol lever cut when filling up even if tank not full

[jt335i]

Try adding some Seafoam to the tank at your next fill up.
Had sort of a similar issue with my 2005 GT Stang where the fuel gauge wouldn't go all the way to full after filling up so my trusted indy mechanic added some Seafoam to the tank. The next day, I refilled the tank and the gauge started reading correctly again.
Hopefully that will work for you.

[bizzleb109]

Thanks

[robthewrench]

The reading on your fuel gauge and the gas (petrol) nozzle cut off are separate processes and one cannot affect the other.

The gas (petrol) nozzle shuts off due to back pressure it senses in the tank as the tank gets fuller and air is pushed out. This is why a malfunctioning tank vent (carbon canister) can make it difficult to fill the tank.

The fuel float only tells the fuel gauge the level of fuel. It has nothing to do with the fuel filling process.

It is possible you have two separate issues here: 1) a malfunctioning fuel gauge and 2) a fuel supply or fuel tank vent issue. Sorry no great insight, other than you'll need to have a mechanic look deeper into the issues. You mention over-filling the tank. This can cause the tank vent to fail and may be related to your current problems.