My '95 starts and runs fine, but shows NO oil pressure. Changing oil and filter made no difference. My '96 maual says the sending unit is both an oil pressure sending unit and a fule pump switch, so I assume the engine would shut down if there was no pressure? Where is the sending unit located on the engine? I could go look but at 15 degrees I would like to narrow it down. If the sending unit tests ok, what is the next step?