I know this is an e28 subforum, but I think the problem I have is not unique to my e12. So, please consider my present challenge. I have an '81 528i: Recently, I noticed that my fuel gauge was off by about 1/4 of a tan. It now shows a level higher by 1/4 than it actually is. I replaced the sender unit, as I thought it was surely the culprit. No so. Currently the tank is very low. But the needle shows 1/4 tank when the engine is running. Odd think is that when I turn the key off the needle jumps down to the actual low level, nearly empty ("nearly empty" is accurate for sure). The needle pauses there for about a second before dropping all the way off to the left of the AMBER reserve lens.This all started, as I recall, the last time I filled it up about a couple of months ago (not my daily driver). I just cant seem to figure out why. Any suggestions you have, I'm all ears...