I did a good amount of searching, including the P0170 All you need to know thread.
I have been getting the CEL P0171 "System too lean" lately, and nothing mechanically has changed that I know of, except having my clutch/flywheel replaced.
My car has a AEM CAI, perrin dp, and AP cb exhaust, professionally tuned in 2010 for 18.5psi. It's currently maxing out just over 9.
When I give the car gas, I get the usual woooosh/pshh sound from the CAI, but there's a secondary sound that sounds like fluttering. There's also (what I think to be) a new sound from underneath the car, but I cannot find the source as my car is extremely low, and even when getting the front end up a small curb, I still couldn't get under.
I checked the MAF sensor, it looks clean, and checked what I could of the exhaust for leaks. I saw water drops where the mid-pipe connects to the y-pipe, could be issue?
not sharing at the moment,.... the original .csv seems to be working..