Please help 1999 318i bmw..speedo not working fuel & temperature gauge flickering constantly...whats wrong???

Hi there.
It sounds like you have a bad connection somewere behind the dash board or on the battery connection box under the bonnet,a loose connection is all it takes.

I fix a lot of clusters. Most of the time it is just a bad connection at the plug. Since you 3 unrelated things, I would guess at this is your problem. Moist bezels around the dash just pop off. You'll have to remove the kick panel under the steering wheel fist, it has screws on the bottom. Just look at the bezels and see if you find any screws