[Stl-986]

Chances are that if you used an aftermarket AOS it's bad, even brand new. Been there. Also, make sure you got the rubber accordian tube on & secure. You will need a mirror for this mots likely.

Best thing to do would be to get the oil in the intake system cleaned out. Use blue paper towels for this. spray the towels with carb cleaner and then clean things. Do it multiple times Clean the plenum as well.

Very much doubt you had oil in the airbox as that would have to make it's way past the TB and the air filter.

Speaking of air filter, what kind is it? If it is a K&N....put it in the trash and get a paper one.

Also check for codes.

You didn't say, but did you actually replace the water pump or just put the other one back in after replacing the thermostat? If you didn't replace it, do it now and get one with a metal impeller not plastic. These are known to fail and cause many people to think the car overheated (could very well overheat). Each and cheap fix.

Worse case, even if you have to replace the engine, you only paid $50 for the car so a replacement engine would still have you well ahead. Doubt you need to replace it though. Just sounds like a bad AOS and a car that has been sitting for a long time.