I have a 2014 VW Passat 2.5L I bought it used last year. It was super quiet and great to drive when i bought it. It has close to 80000 km on it. The past few months I had i sitting in the garage not used. To be precise 8 months in the garage, out of which took it out for spin may be 3 times during that period. car was sitting with small amount of gas in the tank. couple of weeks ago i started using the car again for daily use. But now it sounds way louder than before.
I am wondering what might have happened in the past 8 months of idle time. I filled up the tank as well. i am planning to take to mechanic this week but due to covid situation i am worried to let others touch insides of the car and then i use it so was wondering if i could check things out myself. Any suggestions what could cause louder engine after a few months of idle sitting in garage?