I have skoda fabia 1.2 /2006/ and once i replaced my fuel pump, sensor is working reverse. When i fill the fuel tank it shows empty and yellow light on. what should i do?

Have you connected the wires wrongly, maybe they need swapping over ?

 

I've seen this before on here, and I seem to remember that the level sensor part of the fuel pump changed between earlier and later pumps. A search within this forum for "fuel level" or "fuel gauge" may find it. I think the member's name may have been FromTheDarkness. 

Edited 20 August, 20178 yr by Wino

Sounds like you have the incorrect fuel pump for the car. I had something similar with this when I was transferring parts between 2 cars the level gauge worked in reverse, I moved the other pump over and it worked. I'd recommend looking at the pump you have taken off and check the part numbers between the two.