oil pressure

First thing I would do is punch the oil filters and let them drain looking for metal pull the pan plug and check it for metal, you can just do a plug swap.
It is possible that the pick-up is cracked, or the "O" ring is bad, if it is sucking air, with the valve cover off you will get a popping noise from the air bubbles or foam.
get a good manual oil filled guage and check the preasure, it is possible, the sensor is bad.
Just a thought!

 

Oil pressure sending unit is above the starter, it's easy to change. Mine did pretty much the same thing. I got home the first day it did it and put a new sending unit in and that was it. About $70 or $80

Mike

 

i have a 2000 volvo with a volvo d12 without the egr and i can not find my sending unit any where on the drivers side like volvo dealer said it is
i have been running the truck a few day now but need to find where the unit is so i can replace its
volvo dealer said they could not helo me because they dont have any book that has the pre egr dieagrams in it
so can someone please point me in the right direction or better yet post a picture so i can go by it
some one said it between the one and two cylender do i need to take my alternator off to find it
every one i have talked to said they have never seen or worked on the d12 volvo engine without the erg on it