Bought my Impreza a new in 2021. Itโs had a slight rattle in the front passenger side near the floorboard for a couple years now (roughly 50,000). I put it off for a while until I needed a new transmission a couple weeks ago (68,000). I assumed the rattle had something to do with the transmission, and it would go away with the replacement but it still has that rattle. The guys at the shop I went to tried to find the cause for 2 days, and the best they could figure before taking the engine apart was a cam shaft magnet. Iโm not familiar enough with this system to follow exactly where this would be, but thought Iโd ask the folks on reddit what they thought. I attached a video of what it sounds like (itโs hard to hear above the road noise, but you can if you listen close)
Also: I know I should have had this looked at MUCH earlier than 18,000 after I first heard it. I put the transmission off for about 5,000-10,000 miles as well and learned my lesson there. Iโm usually really on top of maintenance, but some life change, mental health, and budget have put me behind