crazy fuel guage

[garymillscab]

my fuel gauge goes up and down like a yoyo the warning light for low fuel works but the guage has got a mind of its own i have swapped dials from 325i to my 318i woul this effect the guage or what else could be wrong cheers!

[dasparkybad]

i had the same problem with my temp gauge it turned out to be the small nut on the back of the gauge was loose and the gauge did not make proper contact with the main board you will need to remove clocks there is a small nut at either side on the back one holds in the temp gauge the other the fuel gauge check these are tight