Parking opposite our house leaving diesel engine running sounding like a tractor

Driver in Audi A3 regularly comes and parks opposite our house in his diesel car leaving the engine running for extended periods at a time. The car colour appears to be grey under the street light. The time from when this particular driver comes here can range between after midnight till about 4am. At the time of me typing this it is 3:30am. This wouldn't usually be too much of an issue for me personally despite any environmental exhaust pollution impacts aside; however, diesel engines notoriously sound loud like a tractor causing noise pollution and is affecting the quality of sleep for myself aswell as the elderly here seeing that it is running for ages now.