Fuel guage problems, S2Avant

[newsh]

Wondering now if there's something missing from the bottom of the pump so it's not picking the fuel up when low.

It's got to be either that or something wrong with the gauge, I'll have to try swapping the cluster again

[Mikes2]

When you fill up how much fuel are you getting in to fill the tank ?

[newsh]

When you fill up how much fuel are you getting in to fill the tank ?

Good question, I need to start making some notes! The car wouldn't start on the driveway so I put a couple of litres in from a can, then went and put in £50 (38litres) the gauge reads 3/4.
I did discover by comparison with my spare cluster that the gauge adjuster wasn't doing anything, the little gear is loose on the shaft so I'm thinking to glue that in place but I don't really think I'll be able to adjust it to show a 1/4 tank less .. and then it won't show full when it's full either
Strange. I'll run it down to empty with the spare cluster and see how it goes.

[Mikes2]

I'm just getting used to mine since fitting the new sender. I've only filled up once after running it down. Got about 51 litres in and had done about 320 miles

[newsh]

Final fix on this was to replace the fuel gauge damper unit (relay 341 in the aux relay carrier under the dash)

I discovered this little extra part in the fuel gauge circuit by studying the wiring diagrams on S2Central with a view to tracing the wires and checking for bad connections. The “damper” is there to slow the action of the gauge so that it doesn’t go up and down when going round corners and braking. I really had no idea it existed.
I hooked a spare tank sender up to the fuel pump wiring plug and moved it between full and empty positions. Sure enough the gauge would read full but only drop to 1/4 with the sender in its lowest position.
I then unplugged the 341 unit and the gauge started behaving normally (although responding much faster than normal).
I then put a post up in the wanted section for a spare damper and a forum member responded.
The “new” 341 unit arrived, was tried and it works!
I still have to run through a tank of fuel to check full to empty calibration but all looks good.
It’s amazing how satisfying it is to fix a fault like this.
I also found the gauge needle adjuster cog was loose on its shaft on the back of the cluster. I fixed this with a dab of superglue so the gauge position is now adjustable as it should be with the hex key.
Happy days

[Error404]

Nice one John.
My damper doesn't really do much I don't think, the gauge moves around quite a bit with spirited driving. Might look at replacing it