Hey Drewski I have a 94 yoda like yours. 236k and I but 4k on since I bought it five months ago. I changed the oil a week ago not knowing what was put in before I put Castrol High Mileage 10-40. Soon after strange whining from the cam area which would go away. Now knocking from the front of engine. Sounds like I can hear it better from the drivers side. It almost sounds like the power steering pump but it works fine. I took the valve cover off and the timing chain looks fine. When it was rebuilt a hundred thousand miles ago it had steel timing chain quides put in and they looked fine. Not much play in chain either. Had wife turn it over with coil wire removed and it all moved well under the valve cover. Now it doesn't knock/chatter until about five to ten seconds after start up. So for a few seconds it sounds good. Performance and idle are all there still soild and strong but the new sound has it parked in the back. I can take video and Tube it.