Yet another fuel gauge problem

[BAZE30]

Ok I've a weird one. (not that an E30 with a fuel gauge problem is weird or even unheard of.)

Anyways, I have figured out why the fuel gauge shows the needle being empty (no light on) when there is a little less than a 1/4 of a tank still in it. The passenger side level sender doesn't 'seem' to send the proper signal.

I have a spare sender for both sides one so before I put the spare one in, I checked the ohm's reading while it was not in the car and it gave good readings on empty and full. I also made sure the float moved up and down freely up/down the sender. However, I'm not sure what readings I should be getting when full and empty.



I put it in anyway, checked the gauge and I get the exact same readings...WTF

So I snipped a new wire and bridged the 2 connections of the passenger side level sender and again checked the gauge and its showing a little less than a 1/4 tank which is what I expected.

My questions are....

1. Are both my level senders gone?
2. Could I replace the Nichrome wires myself?

Or is the voltage supplied to the senders not enough to give the gauge the correct signal, if so, what should the voltage be going into the sender and then out at the other end?


Oh, I've swapped my cluster too and it has no effect.


If anyone can give me any resistance readings I should be expecting from a FULL & EMPTY fuel level sender?

thanks in advance
Barry

[Brianmoooore]

Senders are approx. zero ohms full and just under 60 ohms empty.
55 litre and 62 litre tanks use different fuel gauges.

[BAZE30]

Thanks Brian,

Just checked there and they're reading in around that.

It must the wiring. Are they known to break in certain areas?

just rechecking the C1 Pinouts of the cluster now.

[Brianmoooore]

No known issues with the wiring.
The two senders may not give the exactly the same readings if measured in situ, since the fuel levels in the two halves of a 62 litre tank may not be the same. That's the reason it has two sensors.
The 'empty' mark on the gauge isn't the left hand side of the orange coloured part; it's the LH side of the part that lights up.
Check that the 7mm brass nut on the rear of the cluster, directly behind the gauge, is tight, or even there at all.
If you have a 55 litre fuel gauge, used with your 62 litre tank, it will read correctly when the tank is full, but will read empty when the tank is still half full.