2006 Sonata throwing multiple codes inc. P0340
 

I have a 2006 Sonata with the 3.3L V6 and yesterday I began to notice a loss of power, then what felt like missfires.
Just as soon as that happened the check engine light came on, she ran even rougher, sputtered and stalled.
I had AAA tow it home and I checked the OBDII codes, they were:
P0340 - Powertrain, Camshaft Position Sensor "A" Circuit (Bank 1 or single sensor)
P1610 - Powertrain
P1676 - Powertrain
P0131 - Powertrain, O2 Sensor Circuit Low Voltage (Bank 1 Sensor 1)
P2B03 - Powertrain

I couldn't find any resource for the last one.
From what I had read, I figured the logical first step was to replace the camshaft position sensor closest to the firewall, which I did this morning.
She fired up, but I hear a tapping sound from towards the top of the engine that sounds like a valve or a lifter, so I shut it off before something worse happened and here I am.
Anyone have an idea at what I might be looking at?
I'm planning on having it towed to a shop tomorrow.