Mini won’t start

Hi guys I’m having problems with my 2008 Mini Cooper diesel it’s automatic transmission 1.6 the car either won’t start at all or if it does it dies straight away. The last time it started there was a horrid rattle noise when the engine revved the code reader came up with $07e8 what apparently is a knock sensor what can’t be right as it’s a diesel an suggestion would be appreciated thanks 🙏🏼