Mine gauge had the needle jump of the coil inside and was reading zero. I just took it apart and reattached it with some tweezers and a steady hand. I verified good oil pressure with a gauge in place of the sending unit.
Be careful when taking the shift position display out its a white rectangle insert that holds the d light bulbs and others my was very brittle and I stole one tab there is two tabs that need depressing to take out. When you pull it out you have do push the bottom into the dash and kinda rotate...