Why does my car make a droning noise when I switch the engine off. It`s only started happening since I had my clutch replaced with a conversion kit as it was previously 'Dual Mass' flywheel. I only picked the car up this morning and have not yet had time to return to where I had the clutch fitted. It may not even be clutch related but it seems strange that it`s only started happening since the clutch was done. Has something not been connected properly?