Bad fuel level sender?

[nadodude]

Preface: The gas gauge on my car works fine and I tightened the already tight nut on the back of the Motometer cluster. I have 16 gallon tank.

I fill the gas tank when the needle is on E and yet the gas pump registers 11 gallons. I don’t run it far enough for the light to come on, but under normal circumstances, anyone would assume the car is almost out of fuel. I know reserve gas is 1.4 gallons but not 5. Is it the sender? Passenger side fuel pump was replaced in 2020 so am guessing it’s the sender on the driver side…

[82eye]

Preface: The gas gauge on my car works fine and I tightened the already tight nut on the back of the Motometer cluster. I have 16 gallon tank.

I fill the gas tank when the needle is on E and yet the gas pump registers 11 gallons. I don’t run it far enough for the light to come on, but under normal circumstances, anyone would assume the car is almost out of fuel. I know reserve gas is 1.4 gallons but not 5. Is it the sender? Passenger side fuel pump was replaced in 2020 so am guessing it’s the sender on the driver side…

do you know which tank you have ?

[nadodude]

Hi 82eye,

Thanks for helping me with all of my issues. You’re the man! I should probably know your first name by now…

According to realoem, I have the 63L tank.

https://www.realoem.com/bmw/enUS/sho...diagId=16_0219

[82eye]

Hi 82eye,

Thanks for helping me with all of my issues. You’re the man! I should probably know your first name by now…

According to realoem, I have the 63L tank.

https://www.realoem.com/bmw/enUS/sho...diagId=16_0219

i think the verts got the smaller tank. not sure they have the space for the larger one with the top folded. did you check it against your vin ? i'm willing to bet you got the 55L or it has been swapped in.

edit : the 55L would be consistent with your experience. the other possibility is you've only got one side of the larger tank active, and the transfer hose is blocked or compromised.

[dworthy]

Should be a 63L tank, as the trunk is where the space for the roof is taken away from. I would think the driver's side fuel sending unit is what's kaput.

[nadodude]

I used my VIN to get to that page on RealOEM to show equipment true to my car. If it is 55L that would be great as that’s one less broken thing I have to fix, but even with the 55L, the remaining fuel doesn’t add up with how much I put into the tank.

[82eye]

Should be a 63L tank, as the trunk is where the space for the roof is taken away from. I would think the driver's side fuel sending unit is what's kaput.

the sending unit doesn't actually pump. it sends signal to the fuel gauge. there is transfer hose and a pipe between the two halves, the intank pump pulls it over from the other half.

edit : looks like the above turns out incorrect. it does pump, but they don't have it on every car. mine just has the one pump, with nothing on the opposing side, and the fuel just transfers through a tube. i must have the smaller tank.

I used my VIN to get to that page on RealOEM to show equipment true to my car. If it is 55L that would be great as that’s one less broken thing I have to fix, but even with the 55L, the remaining fuel doesn’t add up with how much I put into the tank.

if there is no obvious signs of it being replaced then it probably is not transferring fuel from side to side.

[82eye]

i just checked realoem and found the larger tank with the 2nd lift pump. doesn't show up on my car.

dworthy would be correct. check that 2nd lift pump.