Fuel Gauge Problems

efkaba · Post by **efkaba** » 18 Oct 2020, 20:12

Hello All! I have a 1995 850 GLT sedan, non-turbo on which I am having a problem with the fuel gauge. The problem began as a very inaccurate fuel level reading on the gauge. I disassembled the sending unit and found that the float was about 1/4 filled with fuel. It seemed that there was seepage around the center seam on the bottom of the float. Didn't know what to do about the seepage, so I reassembled the unit and reinstalled it in the tank, then went about searching for some sort of gasoline resistant sealant. After awhile, the fuel gauge indicated empty all the time. I found a suitable sealant (hopefully), so I disassembled the sending unit again. This time, the float was completely filled with fuel. I drilled a very small hole in the bottom of the float, drained all the fuel, spread a coating of sealant on the bottom of the float and let it cure overnight. The unit seemed to work fine at first, but now the fuel gauge constantly reads full, no matter how much fuel is in the tank. I followed the Volvo fuel gauge/sending unit troubleshooting procedure I found on line, and everything checks out within specifications. However, there is a stored code, "fuel level sending unit open". The resistance readings on the sending unit are within specifications. According to the troubleshooting procedures, the fault is with the instrument cluster. It seems strange that this as happened after I worked on it, but I cannot find anything that I did that would cause this fault. Was wondering if anyone might have any other insight into this. I always get really great help on these forums, so thank you if you took the time to read this long-winded entry.

Post by **erikv11** » 18 Oct 2020, 20:25

Have you cleared the code to see if it comes back?

I know you have invested a lot of troubleshooting in the old sending unit but at this point I would next swap in a used sending unit from the junkyard. It's cheap and basically guaranteed to be working, so you can go from there to determine if the old one was bad or there is some other problem like with the cluster.

efkaba · Post by **efkaba** » 18 Oct 2020, 20:43

Thanks. I wasn't able to locate a sending unit locally, that's why I tried to repair this one. I would like to swap one out, so I'll probably continue looking.