I also had a scare yesterday. I started my Jeep and the oil pressure gauge did not come up. I started the motor again and noticed that none of the valves were ticking and the oil pump was not whining. replaced the sending unit, and everything was fine again. I would also point out that I priced a new pump as well just in case it wasn't the sending unit, it was only $85. That's an awfully big bill for changing a pump. Just my observation.
"Engineers like to solve problems. If there are no problems avialable, they will create their own .”