2012 Impreza Base squeak

[Faux181]

Hey there! I’m new to this forum and finally decided to write about a problem I’ve been having for months now. My 2012 Subaru Impreza base has been squeaking ever since I got my engine replaced around December of 2020. It only happens when I accelerate from second gear up. I also replaced the stock air box with a cold air intake, but the noise has been there far before I did this. I also replaced the serpentine belt and it still makes the sound. I’ve tried putting a rag in the exhaust to see if it’s an exhaust leak and the exhaust builds up pressure and spits it back out. As I said before I got the engine and the catalytic converter replaced it had no such issue. Although when the cat was replaced they didn’t check the sensors attached to it and one was bad so I had to go back and have it replaced. Also when the engine was replaced they claimed they filled it with Freon, but my A/C didn’t work so they had to fill it up because it was empty. My ac also isn’t as cold as I think it should be. I include all the details about the A/C because I’ve read that the compressor could be going out. When my engine was replaced I had 180000 miles on my car, not it’s at the higher end of 195k. Also my serpentine belt is correctly in place and all the pullies spin, and the compressor turns off and lets the belt run freely when the A/C is off. If you guys could give me some advice I’d really appreciate it. I’ve been through two mechanics and my dad who turns wrenches and they’re all saying different things, so I need some help from someone who knows a lot about my model Subaru specifically. Any help would be greatly appreciated!

[GeneralDisorder]

No clue on the squeak, but put the stock intake back on. Unless you have the car professionally tuned for the (now sure to be) different MAF scaling caused by you altering airflow through the sensor with an intake that does nothing other than allow you to hear a sucking noise and "think" you "feel" more power (you don't - it's in your head), all you will do is wreck the fuel trims, drivability, and fuel economy by causing the computer to try to learn around the sewer pipe you replaced your highly engineered intake with. 

GD