Just refueled my 2015 MK3 octavia, 30 litre diesel fill to full, drove off and realised that the gauge hadn't moved from its starting position, which was correct for the amount I had to put in.

During the 10 mile trip home it slowly rose to just off of full. The trip back involved quite a few speed bumps, but no sudden change in postion happened.

I assume I have a problem with the sender unit, but it is now about where it should be, it just took 20 minutes to get there!

Has anybody else suffered the same problem and found the answer (I assume it is the float and sender unit)

Usually after a fill it instantly responds.

 

Paul

I took my sender/pump unit out last week to drain the tank {don't ask) and it took forever for the gauge to drop down. Do not know why but it always seem to respond correctly when filling. No help to you but I will be watching tomorrow when I brim it.