ht lead arc?

my friends mk1 is winter stored in my garage at the moment. he said she had been driving like a dog and was not happy cold starting.
 couldn't help myself and had to go fiddle.
 the aav is not working and with all the lights out, the ht leads were arcing all over the place. seperated and clipped them so they are not touching anything else but they still glow at the plug end where the rubber meets the metal shroud.
 now just to confirm, in pitch black, i should not see a glow from the ht leads at all, should i?

no i had that last week, ive had cutting out probs from mine, leads didnt solve it but my new ones dont arc at all now.

Cheers

the silicon coating has gone pourous on them, moisture gets in and spark gets out, needs new leads for defo,