Bighead613

Problems:
1. On two different occasions, the engine has somewhat stalled while making a left hand turn. The power steering would quit and the Battery light would come on for a few seconds. After a few seconds (even before I can pull over and stop the car) everything goes back to full power, battery light turns off and the steering goes back to usual. During this whole ordeal, it sounds like something is spinning (but not actually catching anything as it spins) before there's a loud *ca-chunk*as if it finally caught on to what it was supposed to spin.

Note: I went to a couple of those auto parts stores where they tested the battery and said everything seemed to be fine.

2. Mileage per tank has completely dropped off from what it was when I first bought the thing. First few years, I averaged between 290-320 miles per tank while driving about 70% highway and 30% local. I was averaging close to 270-290 on about 80% local 20% highway up to a few weeks ago. Now I seem to average less than 260 but more recently have gotten ONLY 200-210 miles to the tank (on the last two fill ups!!). Mind you, I am no speed racer so I just cant fathom the dramatic decline.


History:
I have not done any maintenance outside of oil + filter changes, air filter recharge (K&N), regular tire maintenance, and brakes (I do need to replace my rear rotors). I have about 69,500 miles on the car.

Question:
Based off personal experience or intimate knowledge, does any one have the slightest idea of what might be wrong and how I might be able to resolve these problems?