Waldo's problem is what I suspected, reading your posts. It could be a massive vacuum leak, which would be a deteriorated leaking or unattached vacuum hose. But once again, Moose says it all. You need a mechanic. They guy you got on "yourmechanic.com" is a hack or a thief. I strongly doubt too many reputable and knowledgeable guys are doing service calls for yourmechanic.com. Real mechanics don't ride around in noisy Hondas selling brake fluid flushes in your driveway.
Since you mention that you're no car wizard, go find someone who is. A problem this obvious shouldn't be too difficult to diagnose for a good guy. Sometimes, Internet forum guesses just aren't enough.
And frankly, no amount of dirty steering fluid, dirty air intake or gas less than three years old would make a car run this way. Steer clear of the nonsense and get someone who can find the problem. In the meantime, look for a disconnected or messed up vacuum hose (generally under a three-quarters of an inch) and possibly listen for a sucking sound where the hose is leaking. The lean bank codes point toward this kind of problem, along with the fact that the problem started quickly.
"yourmechanic.com" ought to be ashamed.
