I have a 1983 mercedes benz 300d turbo diesel with only 129,000k . i been driving my benz for years and this is the only year with problems. my fuel gauge is messed up. when i turn it on it only goes to half and i have a full tank. is there any kind of conditioner or cleaner or anyway i can fix that. i am now going to check my tank by milage but having a gauge is much better i will appreciate the help.

remove the sending unit and clean it..

to do so

remove the first aid kit, then unplug the sending unit.. use channel locks, or a 43mm socket(IIRC)... remove it, be careful, now there is a weird nut on the bottom, use the crush washers to remove it. its a plastic nut but i didnt break mine

be very careful with the wires, notice all the crap in the cylinder... i rinsed mine in kero then diesel then kero then diesel and wiped it all down and used qtips on the wires.. now the guage works like new