lexus-is2

I topped up about 1 litre of castrol 5W-30 oil after getting the low oil warning, checked the dipstick and seemed hard to read but look like it was on the minimum marker. drove the car around. felt normal. next day checked dipstick again and it was confirm that it was in the minimum mark so topped up a further 0.5litres to take it just above the minimum mark with the exact same oil.

Since then the car feels different. from standstill the revs go high even if i gently tap the throttle and when cruising every so often it feels like car is downshifting and getting more power but looking at the gear position it isnt downshifting.

wondering if something is wrong

Toxicxk23

250 or 350? I know the 250 had a carbon build up issue that caused high revs when at idle or at a stop.