quick ? : i cluster in eta - fuel gauge problem

[e30 Luv]

so i picked up an eta a couple months ago and it didn't come with the gauge cluster. so I installed the one I had from my old 89 i. it works fine in that I haven't had any speeding tickets or anything. but the fuel gauge has never worked properly.

When the tank is full, the gauge shows full. When the tank is empty the gauge shows 1/2. Is this a problem with the gauge, or the sending unit?

[Teaguer]

Sounds like the sending unit .

Did you replace the coding plug with an Eta one or is it showing to rev up to 6.5k ?

[e30prideTN]

I have this same exact problem, but I just used it as is.

Does this mean at 1/2 tank, it's empty? Or is there still have a tank?

[e30 Luv]

no, I didn't change anything when I installed it. Actually I don't know what the coding plug is :oops:

any way I can test the sending unit? Bentley didn't seem to have a test for it.

When the tank is empty the gauge shows 1/2

[jlevie]

You can remove the sender from the tank and check its resistance with the float at the top (sender upside down) and at the bottom (sender right side up). I think that later cars (post 9/87) may use a sender with a range of 0-74ohms. My 6/87 325is uses a sensor with a range of 0-58ohms. So there looks to be more than one sensor/gauge combination. Oh yeah, the sender has zero resistance on a full tank.

I've got the same problem and I'm pretty sure at this point that it is a mismatch between the gauge and sender, One of these days I'll see what fuel gauge I currently have in the cluster and see if I have one from an early production (having a few clusters on hand can be handy...). For now I'm just living with it.