I would have a leak down test done to determine what is going on with the cylinders or valves....Somebody must have never changed the oil on that puppy. Lexus engines are know to go forever and without using any oil....I have had two that used none. One at 187k miles and my present one at 161k miles. Good luck.
If you added 2 quarts and nothing is showing, something is way wrong. I use New Jersey's Lemon Law and return that puppy as soon as possible. Lots of cars for sale.