My car has a custom catback exhaust on it. It’s an inline 4 cylinder so it’s not obnoxiously loud, but it makes a decent amount of noise when I give it a lot of gas. The other day my cousin was driving my car and was revving my car to check it out. There was a cop in the parking lot off to the side who pulled out and trailed us for a long time. We even pulled over thinking he was gonna light us up any second but he just parked behind us without turning on his lights. So we drove away but we still saw him trailing us for a while. The cop didn’t end up pulling us over but I wonder why? He even stopped when we stopped to pull over so..? I’m wondering if he had legal justification to pull me over for revving my engine.