Hello . I'm new in this forum . I'm from dominican republic ,i have a skoda felicia 2000 glx with a bad fuel gauge or fuel sender . well the problems is that the fuel gauge always shows 1/2 tank ,when i turn on and turn off the key the gauge shows the correct level ,but when the car is running the needle goes to the midle no matter how much gas is in the tank .At the fuel sender I have three wires yellow ,blue and green , the blue wire goes to directly to the fuel gauge and the green is connected to a yellow wire in the fuel gauge. the yellow wire at the fuel sender is connected to earth , I was reading in here few topics about fuel gauge and sender problems and the yellow wire is not connected to earth.

I measure with a multimeter the voltage of the wires : blue =8.03 volts ,green =3.23 volts , yellow nothing. I am really confuse about these connections . I would appreciate any help with my problem .Sorry for my bad english ,Thanks.

Find attached the wiring.

1) Check fuel sender with an ohmmeter. It should have a total resistance of about 430 ohm. Check cursor for smooth riding.

2) Check wires for continuity from sender to gauge. Check for short-circuits.

3) Check gauge, replace with a known good one if any.

My guess it's bad wiring, earth wire most probably. If not, the gauge is shot.

Edited 9 November, 201213 yr by adurer

Please disregard previous wiring.

Here is the correct one.

Edited 9 November, 201213 yr by adurer

Please disregard previous wiring.

Here is the correct one.

Thanks for the wiring diagram you help me a lot with this picture . I measured the sender resistance with an ohmmeter and the value is 451 ohms , i think is not too bad. I'm going to test the gauge and re-wire with new cables from the fuel gauge to the sender .

The fuel sender resistance is Ok. It is more important the cursor rides smoothly making contact from start to finish.

Here you have the entire process of testing the fuel sender/gauge system.

Keep us posted about what faults you found.

Edited 10 November, 201213 yr by adurer

Thanks Adurer for your help . i did the entire testing process and i found the problem.The sender is bad ,in the sender there is a little coil of copper wire ,basically is like a rheostat or a potenciometer and this little copper coil is rusty .the float arm gets stuck at a certain point . thats why my fuel gauge always shows midle level .I tried to clean and lube but it doesn't work.I have to replace the sender . thank again for the wirings.

From my experience, fuel senders on Felicia are built to last, they are lubricated by fuel itself. The cursor is made of spring steel plated with copper, the resistor is made of high resistivity nickel alloy. I don't want to spoil your party, but a bad/stuck fuel sender doesn't make good readings when key on like you said, then gets stuck at 1/2 tank in motion, under vibration...

I have somebody here with the exact same problem. He replaced fuel sender with a new one and the gauge still shows 1/2 tank.

Let us know what happened after you changed it.

Thanks Adurer for your help . i did the entire testing process and i found the problem.The sender is bad ,in the sender there is a little coil of copper wire ,basically is like a rheostat or a potenciometer and this little copper coil is rusty .the float arm gets stuck at a certain point . thats why my fuel gauge always shows midle level .I tried to clean and lube but it doesn't work.I have to replace the sender . thank again for the wirings.

Can we confirm, you're saying that the coil is blue (default Windows XP header bar colour) or green (the lighter of the 2 shades surrounding the messages)? If it's neither of those colours, it's not corroded. There's a very outside chance of the rheostat coil having worn out, but I'd need a photo of the sender from the sweep side to confirm that.

Well , let me try to explain it better . when I said that the float arm gets stuck at a certain point is because there is a little piece of metal that is attached

to the float arm that is hitting the copper resistor and no matter if i have full tank the cursor stop at this point ,only when the fuel level drops to 1/4 of tank the gauge shows the correct level. .

You're making this sound like you've got a mechanical problem with the sender stopping it moving full scale, but the guage reads correctly in the bottom quarter of the tank?

If so, well I'd live with it, and use the trip mileage as an approximate indication.

I might be able to advise on fixing the sender, but I'd need some good, clear photos showing it.

You're making this sound like you've got a mechanical problem with the sender stopping it moving full scale, but the guage reads correctly in the bottom quarter of the tank?

If so, well I'd live with it, and use the trip mileage as an approximate indication.

I might be able to advise on fixing the sender, but I'd need some good, clear photos showing it.

Hi . I found this picture on google , this is exactly what is happening with my fuel sender .The float cursor gets stuck at a point like the circle in the picture ,the only difference is that my resistor isn't open .I can rebuit using the same copper wire and count how many turns i have to do . If it doesn't works i have to buy a new sender or used one .

It would be so much simpler to take a photo of your own sender.

The sender resistance (which has some 90 turns) is NOT made of copper, it's usually made of 80% Ni + 20% Cr for high resistivity.

You make it of copper and you'll end with a 5 ohms resistance max!

The copper colour is most probably due to some electrolysis coating.

Hi . I found this picture on google , this is exactly what is happening with my fuel sender .The float cursor gets stuck at a point like the circle in the picture ,the only difference is that my resistor isn't open .I can rebuit using the same copper wire and count how many turns i have to do . If it doesn't works i have to buy a new sender or used one .

Frankly, if the resistor track is that mangled, it would be faster, easier and cheaper to buy a new sender than to establish the correct resistance per unit length, source the correct alloy and thichness, and re-wind the coil yourself.

Frankly, if the resistor track is that mangled, it would be faster, easier and cheaper to buy a new sender than to establish the correct resistance per unit length, source the correct alloy and thichness, and re-wind the coil yourself.

Yes . I know is better toy buy a new sender.for now i only use the car four days a week and I know how much fuel the car spend. Well I'm getting about 28 mpg , I have an engine swap from another brand .My felicia has a D15B 16 valve single downdraft carburetor from a honda civic 91 in my country this kind of swaps are very popular you can see a lot of cars with other engines such as toyota ,nissan ,honda everything what you can imagine.I did this swap because the cylinder head of the skoda engine was bad and I could'nt found a used one in good condition and a brand new head cost the same as the entire honda engine with gear box.

The car runs pretty good with this engine its about 91hp and i have some mods .I like european cars but in my country the parts of this cars are too

expensive.

Thanks for your help this is an excellent community. If you want I can post picture of my rare engine swap.