2009 Pontiac G6 GT 4spd Auto with 181k miles

Hey guys, I smell a terrible odor of burnt oil when I accelerate hard. I don’t think I am losing oil yet then I check under my car and there’s never any oil dripping or never any puddles but there’s a thin layer of oil that’s coating the underside of the engine oil pan and some other parts. It’s hard to tell where it’s coming from and I think it only leaks under high crankcase pressure because I only smell it after having accelerated hard. Like 75% throttle or more even at low RPM.

For example I will drove my car in a lower gear and accelerate above 75% throttle and I don’t even have to exceed 3500rpm and when I slow down or come to a stop I can smell it. Especially if the window is open.

So I was wondering maybe a bad gasket or seal? How do you go about finding a small enough leak like that? I constantly check my engine oil level and it usually drops about 0.5 qt every 3-5k miles by the looks of it. I had always chalked it up to the car being high mileage.

What do you recommend? As a college student I would need to replace the parts when I get the money.