Have a Nissan with oil pressure problems on 1995 Nissan 240SX

The cam pully came off and was replaced and also had oil, filer change and a few hours later the oil filter popped off and lost all the oil. But did not run engine but a few feet before it was turned off. Installed new filter and oil. same thing happens. What is wrong?

Asked by for the 1995 Nissan 240SX
1 answer
oil pressure is pegged and not being regulated. oil pomp should be checkked by a shop.