325i issues

1) The right turn signal of my 1988 325i flashes very quickly on the dash, but does not work on the exterior of the car. I have replaced the flasher under the dash, but I still have the problem. Do I need to replace the turn signal lever?

2) How do I get the programmed "change oil" light to turn off?

3) Where is the fule filter on this thing. There is a cylindar on the driver side 1/4 panel, but it is not the filter.

Any ideas? Thanks!