What would cause a sudden loss of power AND the AC to start blowing hot air?

Driving home yesterday, 60mph or so, I changed lanes and as I gave it some gas, I had an obvious loss of power. It was still running, a little choppily, but going slower and slower. Then I noticed the AC blowing warm air, so I turned it off. I managed to get it home, but it had no power going up a small hill or accelerating. It still starts fine. We got a code read from Auto Zone: P0352, Ignition Coil Primary Circuit Fault - Cylinder 2. We have changed the coil, but it didn't help.

Any ideas?