Approach this little beauty in a systematic way, after each check see if it has cured it before you go onto the next thing.
Check the connector block on the right hand side just under the tank. Pull it apart and check for frayed wires or corroded connections. Make sure all connections in this block are clean and good. This is likely to cure it.
If its not this then its either the sender unit on the fuel guage or the lcd display or the wiring in between. It could even be a kinked crossover pipe cos its an Adv. Has the tank been fiddled with at all recently?
Heres a parts picture for you .... The bottom pic is the back of the sender showing the potentiometer under the float arm.
Check the connector block on the right hand side just under the tank. Pull it apart and check for frayed wires or corroded connections. Make sure all connections in this block are clean and good. This is likely to cure it.
If its not this then its either the sender unit on the fuel guage or the lcd display or the wiring in between. It could even be a kinked crossover pipe cos its an Adv. Has the tank been fiddled with at all recently?
Heres a parts picture for you .... The bottom pic is the back of the sender showing the potentiometer under the float arm.

