Hello I have a 1990 subaru legacy with a standard 2.2 in it i wasnt driving it for 4 or 5 months except around the block every day then when i was going to start driving it all the time i changed the oil and now it has a high pitch screetch and knocks alot what could have gone wrong? I used napa 5w30 same oil i have used since I got the car no check engine lights on just the noise please help, Thank you

Describe the knock.

 

Check the oil level.

 

 

nipper

If you think the noise is the engine itself, maybe it circulating oil. Was the engine oil filter changed as well? If yes was any engine oil poured into the filter or was it just put on dry?

Is the noise a knock or a tap- if it is tapping the hydraulic lifters may have bled down from sitting so much. As far as the screeching- check the alternator/PS pump belt- may have gotten a little oil on it, could need adjustment/replacement. True knocking from the oil pan area means the oil pump could have lost it's prime and is not picking up oil (not that common on Subarus but does happen during rebuild on some GM engines).