Hi to all- i have a C200 mercedes elegance year 1999-the gas meter isnt working right-its either always full or half empty regardless of the actual quantity of gas in it. Im not all that familiar with the exact names of the different parts so bear with me plz-the mechanic told me that there was a problem with something inside the gas tank thats responsible for indicating the gas level-there are 2 of these in the car-he changed them both. i drove the car for a couple days and found that it still isnt working. so i went back-he said that it has to be reprogrammed on the scanner, so i did that and it still didnt work. so i went to a different guy and he also changed the same 2 parts plus he put in a new dashboard and said that it might be something electrical. i have driven almost 200 km so far and the gas needle barely budged.

What do u guys think?????? whats wrong with my car???

The way these work is that there are two sensors. The average of the two is the fill level. So for instance if one is all the way full and the other is empty then the gauge will read half tank. There is a siphon tube that sucks gas out of one side into the other as fuel is pumped out and returned. It is most likely that the siphon tubes are damaged or kinked. I have also seen these gas tanks need to be replaced. A good way to diagnose is that the one side of the tank will always be full. When the technician drains it they should be very close to even fill level.

Good luck

The 99s had some issues with instrment cluster not being compatible with the new style fuel senders after you replaced them you had to change both senders and instrument cluster.Late in 99 the style of senders was changed
Bulletin from 5/2000
MODEL YEARS CLUSTER FSU - LEFT FSU – RIGHT
202.023 / 98 *202 440 46 11 202 470 26 41 202 470 30 41
202.024 / 99-00 202 440 46 11 202 470 26 41 202 470 30 41
202.024 / 99-00a 202 440 47 11 202 470 26 41 202 470 30 41
202.029 / 98-00 202 440 50 11 202 470 26 41 202 470 30 41
202.029 / 98-00a 202 440 51 11 202 470 26 41 202 470 30 41