Originally Posted by Stevo666
…….Or the other thing it can be is especially common on Euro4 cars, the cats come loose and rattle. Had one where 3 of the 4 cats had come loose.
If that’s the reason, then it’s likely to be an MOT failure, so best not to ignore?

Doug
2011 Plus 4 in Rich Maroon

1972 750 “ComDom” sprinter
1958 Triton 650
1992 Triumph Trophy 900