My saga continues, I had posted here about my 1999 sentra that I discovered had a ton of sludge when I removed the valve cover to check the timing chain. Well afer reading the cements posted here I went to my local salvage yard and found an engine from a 1995 sentra with 130000 miles on it and when I removed the valve cover it was as clean as the day it left the factory, I am dumfounded, I would not believe it if I did not see it myself. No crud or discoloration of any kind. I bought it for 200 dollars. I took pictures with my camera but cannot get the software to load them onto my computer, but I will keep trying. Part 2, I will not be able to swap the engines for a while so I thought I would try some of that new Pennziol Plus that removes sludge. I removed the oil filter I put on last week when I changed the oil after trying th RX treatment. Well guess what, there is no oil in the filter. I checked and the oil passage is open, so know I am wondering if the problem is the oil pump and will check the pressure. I have put about 200 miles on the car since I put the new filter on. Just so you know this was supposed to be a spare car to drive in the winter, that is why I am trying to fix it on the cheap.