I was wondering how long has it been happening? Did it possibly start shortly after changing oil & filter. This is an occurrence, that seems to happen on them. I have read quite a few reports on this happening. Usually, the suggestion is the sender unit, but I don't think that is the problem. There has been mention of the oil filter causing the issue. What kind of filter do you normally use? As of yet I haven't read of anyone replying with the fix on any particular one.