Strange petrol gauge issue

[PeterMercedes]

My Vitesse was almost out of petrol. Filled right up and now the gauge indicates empty. Temperature gauge works ok.

Could it be that the float in the tank has caught on something in there? Might this clear itself ?

[johny]

Certainly worth driving it around to see if theres any change and also lower the fuel level enough so that if necessary you can get the sender out.... In the meantime you could short the sender supply wire to earth to confirm the gauge then reads full.

[Dick Twitchen]

Hole in the float or it has detached itself from the arm?

[Badwolf]

I had a similar problem with an older toyota. Fill up, guage reads empty, get to half way and guage reads half and then drops normally. Sorted it in the end, sold the car... but not really the solution that you wanted to hear.

[NonMember]

11 hours ago, Badwolf said:

I had a similar problem with an older toyota. Fill up, guage reads empty, get to half way and guage reads half and then drops normally.

Yes, that's fairly common. It's caused by contamination / dirt / corrosion on the upper part of the sender track. The sender is just a variable resistor made of a wire wrap (or carbon track) with a wiper arm. If the wiper isn't making good contact then the resistance goes high and the gauge reads empty. This is quite easy to diagnose if the sender is out of the tank but you'll need to empty the tank before doing that.

[Badwolf]

I also had a Hillman Imp. You could tell the tank was getting low from the all pervading smell of petrol which occurred when the gauge was low. Got rid of that quickly too.  Must say that both Toyota and Hillman were part exed, not sold privately. I assume that the dealers dealt with the problems,

[Pete Lewis]

on a vit/herald  its reasonably easy to fish for the float arm via the filler and you can lift or sink it to check its operation without draining . 

dont use a candle to see where youre at, 

 but a stiff wire will make a probe   or a small led illuminated mirror can be useful

Pete

[ahebron]

I suggested the use of a torch for looking into a fuel tank on an American site.
Different meaning of the word torch apparently.

Adrian