Erratic fuel gauge needle

Hi all,

Apologies for starting another thread but I love the helpful discussion on the forum!

Has anyone discussed the inherent X1/9 erratic fuel gauge needle bounce before?
Is this something that we just need to put up with or is there a cure for it?
Thanks,
Gaz.

Hello,

I’ve had two Fiat 132s with a similar fault. On the older car a 1974 1600GLS I could see it was worn out, there was a thin copper wire wrapped around a part of it which had broken in a few places. Replacing the fuel gauge sender unit in their fuel tanks fixed both cars. I don't know if you can test or repair them.

My 85 has always done that. Even 35years ago that was what the gauge did, now replaced sender 4or5years ago, it still does the wiggle.
I guess it is down to the tank design - it is tall and thin rather than flatter dimensions.
The dynamics - damping of the gauge plays a part in how the needle responds and our Fiat gauge is underdamped.

I did give some thought to designing a wee microcontroller circuit to average out the gauge over say 30seconds and to calibrate the gauge to better reflect the tank contents but I haven't - yet! I also saw a simple electronic circuit to better linearise the oil pressure gauge and thought about the petrol as well, but... I just live with it.

......I might just leave it then.

Thanks,

Gaz.

Hi Gareth,
The fuel does slosh around in the tank a bit. There are no internal baffles to stop this, so that may cause the fuel gauge to jump around a bit.

So!, there are three possible solutions:
1. complex electronics to electronically / microcomputer to damp the gauge
2. only use the very thickest slurpiest grade of petrol
3. Don't look at the fuel gauge

......LOL......after a lot of thought and weighing up the pros and cons, I think I'm going for option 3!

Gaz.