ELINT by our ( & possibly other peoples' ) sub's yes as far as I know - but how was even a U.S. carrier going to accommodate an E-3 ?!
I rather doubt the U.S. wanted assets other than satellites too near.
If R.N. TLAM's had been available, it might have been extremely tempting to chuck some towards the Arg' airbases, in conventional cluster mode, though that would mean a distinct escalation; as it was I understand we sent some people even more problematical for the enemy, though mainly in a recce' role - full story yet to be released to the likes of me.