I can't seem to figure this one out. My engine light will pop on for a day, go off randomly for another day, pop back on and off again. I check the codes and I get 171 and 174, system running too lean on both banks 1 and 2.

 

Try cleaning your MAF sensor and screen with some MAF cleaner. I had the same problem shortly after I bought my car and it fixed that and it ran noticeably better than it ever did since I got it.

 

Another thing to check for if both banks are too lean would be a vacuum leak.

 

I just checked my MAF, its clean. Its actually only a month or two old. Is there a good way to check for a vacuum leak? And this may not have anything to do with it but I noticed my car leaked some kind of oil (looked like dog urine when when i soaked it up with a paper towel). I took a oil sample from under the hood and the color didn't match...

 

Let the car run and get some intake cleaner and spray it around all the hoses and the intake system. If the idle changes, surges, or stumbles, you've found your leak.

Since you're not getting many responses you could do a search on MAF's too. I remember hearing of people having some problems with aftermarket ones.

 

another good way to check for a vacuum leak is with a bottle of propane the gas will make your idle smooth when you find leak little cleaner method than the intake cleaner old school...

 

My light just when off again... hmm. Would a vacuum leak cause my car to be kind of sluggish? For example, lets say im cruising at 50mphs in 5th, and i then i floor it, my rpms will go up about 750, the engine will get louder and then it will drop down about 500 rpms and start to go up again.