petrol gauge ?

[kinkyfreestyler]

Hi , need help with my petrol gauge . For some reason it has started to read backwards i.e it says full when empty but the reserve light come on when its full ? it still drops to the left when the ignititon is off ?

Strange ! there's no wiring loom diagram to be found anywhere ? so doe's anyone out there have a clue. I don't want to be messing with the 3 wires going into the fuel pump, because if I burn it out ,it means taking the tank out to change the pump and sender .
thanks

 

[Vbob]

I have exactly the same problem. Mine started when the fuel pump was replaced. First fuel pump replacement gave me totally inaccurate and stuck fuel guage. So they swapped the fuel pump for one or two other ones (can’t remember exactly how many tries there were) but the outcome was that the current fuel pump gave me a gauge that worked backwards - reading empty with light on when full of petrol and reading full when empty! It’s not ideal but more accurate than when the first replacement pump went it! I don’t mind putting up with it like this all the while it’s accurate, just backwards, if you see what I mean!

 

[John Woodward]

I believe that there are 3 types of fuel pump/sender units. That's why in my opinion it's better and cheaper just to replace the actual pump.
When I had my Thunder, the wrong sender had been fitted and the gauge wouldn't go below 3/4 tank, luckily the previous owner had given me the original unit with the dead pump, so I fitted the working new pump to the original sender unit and all worked correctly.

 

[YOG]

Hi , need help with my petrol gauge . For some reason it has started to read backwards i.e it says full when empty but the reserve light come on when its full ? it still drops to the left when the ignititon is off ?

Strange ! there's no wiring loom diagram to be found anywhere ? so doe's anyone out there have a clue. I don't want to be messing with the 3 wires going into the fuel pump, because if I burn it out ,it means taking the tank out to change the pump and sender .
thanks