406 V6 fuel gauge fluctuates

My fuel gauge is very stable and does not fluctuate. I guess if the change is this rapid then it must be either a loose/bad connection or a faulty sender unit.

Regards G

G, what model/year do you have? Mine is 1998. The whole instrument panel/unit had been replaced for the previous (original) owner by the new car dealer.

I just returned from a long trip in my 406 V6 and I noticed that the fuel reading varied a bit - nothing like as much as yours though. It is usually possible to make the particular trip and return on one tank-full. I noticed as I was about to leave on the return that the gauge showed a little less than half-full. But, within 50km or so, it was above half. OK!

Later, in the same leg, it was markedly down - so much so as to raise doubts as to whether I would make it home without a transfusion. But then it seemed to correct itself and I made it home well before the fuel warning was activated.

I assume that the 406 fuel gauge is driven by the same sort of sender which has been in use for decades - one which translates the fuel level into a resistance. If so these variations may be due to a sticking potentiometer or, maybe, to changing voltage level - the latter would account for the reassuring improvement in my fuel reserves soon after departure.

Thanks Ken It sounds as if your gauge is behaving in a similar manner to mine, which could suggest a design factor is involved. I am keen to hear from other owners, particularly V6 owners, just to compare apples with apples.

Mine is perfectly accurate, so I don't think it's a design-factor !

Well mine is sufficiently accurate - the errors were on the safe side. And the variation was small - from just below half-a-tank to just above. Sedan.

I can accept that. I am still getting used to a 'gas-guzzler' compared to the Fiat Punto 1200cc that we otherwise drive around the city! My biggest car previously was a 2000cc.

Mine moves very erratically. 406 LXDT 1998

Thanks Madrigo Padrigo. Same year....interesting.