Fuel Gauge stopped working

[abbot]

It shows empty even after filling. Just started showing the problem today. I did a search an could only see problems with gauges reading full when empty. Is it more likely to be gauge or sender?

[myothercarsa2cv]

My money is on the sender. If there's a float, it's probably not floating

 

(From experience with flaky 2CV stuff )

 

Edited by - myothercarsa2cv on 5 Jan 2014 23:30:21

[elie boone]

Could be a earth problem on the fuel sender, to check the gauge : just ground the wire from the fuel tank and it should indicate full.

[Stationary M25 Traveller]

Lift the boot floor .... favourite probably wire broken around the connectors on the sender or the earth connection there. Assuming your sender is on top of the tank.

[tangomikeromeo]

I had a simliar experience late last year - resolution was a good jolt courtesy of a pothole which evidently freed the float.

 

So far, so good.

 

Not sure how you engineer a potholesque jolt if you have properly maintained roads though.

[abbot]

thanks for the comments, the job is scheduled for the weekend

[abbot]

Here is a summary of this mornings problem solving activities:

 

1 Upside down under the dash to try to see if anything is loose. Nothing looked out of place but solved another problem. There is a large plastic cylindrical tube that the harness goes into, it was rattling about behind the wiper motor, moved it and tie wrapped, annoying rattle from behind the dash now quiet.

 

2 Removed boot floor to get access to the top of the tank

 

3 Took the terminals off the sender unit and shorted them together - Fuel Gauge goes to the full condition: Conclusion Fuel gauge OK

 

4 Removed the sender unit from the tank and tested the resistance with multimeter: reading goes up and down consistant with the position of the arm: Conclusion Sender Unit OK

 

5 So if gauge and sender are ok unless it is an intermittent problem in the harness it should work

 

6 Put it all back together and it worked, but while screwing down the boot floor it stopped working. so lifted the boot floor again

 

7 on the female spade connectors I pinched closed the terminals a fraction. This appears to be the root cause of the problem as I put it all back together, went for a blat and all works OK

 

Problem Solved

 

 

[Birkin S3 ZA.]

I am sure It wont be like my one sticking

One of the rule changes for racing was only plastic fuel tanks are allowed, the trouble is they distort quite badly with the reaction to the petrol.

Mine has concaved on the front flat section enough to jam the float, I adjusted it and it has now concaved even more and jams it again 😔

Chris

[Z3MCJez]

Chris

 

You don't need a fuel gauge to race!

 

Jez

[Birkin S3 ZA.]

You don't need a fuel gauge to race!

It 50% road and 50% race with the occasional endurance race when we need to know how much we have left, as for sprint races we just run enough + 5l per race.

Chris.