My scenario was that I removed the valve cover, and now it smokes alot of oil. The consensus on another board was also the rings, but I'm not ready to throw in the towel. After reading this thread, I checked the resonator, which on my Mazda is just a little box attached to the the air filter. I didn't find any oil, but it did lead me to checking the pcv valve which did appear to be swallowing oil.
I tried to unplug the pcv and run it for awhile but it didn't seem to clear up.
At this point I'm still hoping it's the valve cover gasket. My theory is that it's providing enough of a vacuum leak to cause incorrect pressure on the underside of the piston and forcing oil up through the rings. This would explain why cylinder #1 is the cleanest and #4 is the dirtiest, with 3&4 fouling from oil; because, they are the furthest away from the vacuum source.
I know it's a long shot, but it actually is making the most sense. I'll let you know what I find. The cover gasket is on order through Mazda and should be here tomorrow. I'll also replace the pcv, and pop another new set of plugs in.
After that it's compression test time... but I still have a hard time accepting that answer since my problem occurred almost immediately after removing the valve cover.
I would have accepted the PCV being the sole problem, due to the oil in the line, except for the fact it continues to smoke. That would require it pooling in something (like the resonator) which I've checked and it's fine. Unless there is somewhere else for the oil to pool in that I'm not thinking about.
If you come to any conclusions, please post your outcome, I'm burned out from problem solving, and completely scared of the possibility this could be internal engine damage.
