What you didn't indicate was time periods between when you last checked. Its hard to believe that you can add 2 quarts to get a "good measurement" as opposed to the "multi attempts" prior to that which gave "irregular measurements". My guess is that the system is / was low and your "multi-attempts" were picking previous "leftovers" in the tube which eventually you read as "good". With the "no pcv valve" operation, oil "loss" won't necessarily be noticeable but will eat thru oil in most cases.
Of course, depending on when the last change might have been (or last add), you could have done a "official check" by doing a change / drain / measure, then you could have confirmed where the oil was or wasn't.
This is a good point. How many miles / how long a time since your last oil change and fluid level check? This motor does consume oil - some more than others. There are also several leak prone areas such as the valve cover, coil valleys, etc. If you burned/leaked 2 quarts between oil changes (3000+ miles) I wouldn't be surprised or disappointed. If you burned/leaked 2 quarts in a few hundred miles you would have other symptoms: bad spark plugs, plugged catalytic converter, fluid in the plug valleys, noticeable quantities of oil wherever you parked, etc.
My preferred oil check is after the car has sat overnight. I check the oil without starting/running the engine and without moving the vehicle. Literally, I pop the hood and pull the dipstick, clean and replace it, then wait a second or two and pull it to check. 95% I'll get a good clear reading doing just that. If not, I'll clean and reinsert, then spin the handle 1 full revolution while fully seated. Then pull and check. If I find that it's "dry" below the middle of the range, I'll add either a half or full quart depending on how low it is.
Having been ~nearly~ stranded due to vehicle faults on more than one occasion as a youngster I now keep in my vehicles things that seem silly to some, but help increase my chances of getting home without a tow bill and without sleeping in the car. 1 full quart of motor oil - NO LESS. 1 used but serviceable fan belt (when you change one, keep the old one). 1 used but serviceable low beam headlight bulb (gets you home, can get you out of a ticket in some cases). 1 used but serviceable taillight bulb (ditto). At one point in time I also carried a pint of brake fluid, a full quart of transmission fluid, and a quart of power steering fluid but over the years I found that if I needed to add brake fluid while out and about, I shouldn't be driving the vehicle (proportioning valve failure, 100% fluid loss). If I needed to add power steering fluid whatever quantities I would add would soon leak back out (split the rack once, broke a fitting once). The transmission fluid is another matter. I once nursed my bravada 25 miles to my destination stopping every few miles to add a full quart of transmission fluid - I bought every quart the rest stop had and used almost all of them. My transmission line had rusted through and fluid was "raining" on the back window (and pissing off everyone behind me). The next day it took almost 5 quarts of transmission fluid to get it to the dealership 5 miles away. $500 and 2 days later I got my car back. Bastards even charged me for a car wash. I now no longer carry transmission fluid with me because I've gone over every thing I can with the tranny to make sure I don't need to - including new lines, pan gasket, dipstick grommet, etc. If I need quarts of tranny fluid now, it's probably toast.
If you were LEAKING a lot of engine oil you would see oily deposits on the hatch. If the hatch is dusty, look for discolored spots where the dust and oil mix - they'll be slightly darker than the surrounding areas. The rear window will also show it but if you use your wiper it may appear as streaks that won't go away or get "creamy" when you use the wiper.
