I have the same car/engine set up only a '95. My air conditioning didn't work, which I didn't care until summer hit. Iowa summers suck I tell ya. Maybe not as hot as Cali or Texas, but the humidity I swear would kill somebody. Anyway, they said it shouldn't stop working unless it's leaking, and if I noticed a drop in performance to bring it back. Well, it's been two years and it works great still!
My point is though, that it was the same for me, I got zilch from it until I had it charged.
Tony