Have p0306 and p0316 error codes.

What is your question?

Have replaced coil, spark plugs, injectors, etc... You name it, it's probably been replaced. Horrible gas mileage, smells rich, rough idle, car will quit as a stop sign, within the first 7 mins of starting (idle), it will shut off. Help!!!noone can seem to figure out the problem and I am very frustrated with having to spend money that is not actually needed. I could have purchased a new engine for as much money I have put into "fixing" the problem that still exists.