I have a 97 Civic EX with AC.

When i rev the engine to ~4000rpm and AC is off, no problem, but when i rev it to the same rpm range and AC is on i get a loud squealing type sound from under the hood.

My hunch is a possible worn belt. Would anyone know if there is anything else that, given the same situation, might do the same thing?

Thanks for any info.

PS --- unsure if this is right location for post, but engine tech seemed right to me since the sound seems to be coming from under the hood.