Loose wire from starter and alternator query

[danny_p]

if you don't have one it'll sound like youve got a littel supercharger when the radio is on

[gtigolfthree]

1. That terminal is only live when starter is engaged and helps engine start as already mentioned, wont affect normal running as it only works with the starter.
2. As above a suppressor, the brushes on the alternator can arc which interferes with the radio, motors do this too eg wiper motor.

[Ant]

All understood, thanks everyone for your help