Engine clicking & P0505 IAC & acceleration issues

I have a 2006 Prius, am in southern california, and my car has 206k miles on it. First, I was getting the p0505 code -- I cleaned the throttle body to start, but was still having issues, we also noticed that there was also gas and oil mixing in my engine, and a clicking sound (not banging or knocking).

Clicking: it clicks when the battery is running and accelerating, louder when it is cold/idling, lower when I am driving for a long period of time.

IAC: I changed out the throttle body and sensor (swapped full part), the clicking is still there, the acceleration issues are still present, though not as bad.

Acceleration: Before swapping the throttle body the car was sluggish, my gas mileage was around 27 mpg, when usually its around 34 mpg.

Battery: not charging more than 3-4 blue lines, most often it is in the 2 purple. It will not get in to the green.

From suggestions from a mechanic friend: I will be filling up with premium gas and putting fuel injector cleaner in it, after that, I will change out the spark plugs if needed, and I need to test the 12 v battery (about 2-3 years old).

Has anyone had this issue? Suggestions, other things to check would be super helpful.

**I have had the hybrid battery replaced, the catalytic converter fixed with in the past year**

 

Update:

12v battery is in perfect working condition.

I started and drove about 1/4 miles, and the car stopped. Pressing the gas did nothing, the car only went in to park and neutral. I turned it off for about 5 minutes and it started normally. I was able to drive it back to the house and park it.

all dashboard lights went on immediately when it first stopped.