About a month ago, my 2011 WRX threw CEL code P0171 (System too lean). Only real symptom was a very rough idle that only happened after restarting the car after filling up at a gas station. Brought it to the dealership and they replaced the engine filter, serviced the MAF sensor, and unclogged a vent hose in the gas tank for the rough idle.
Now it's a few weeks later and the CEL is back. This time they want to replace the intake gaskets and say it requires pulling the engine to do so, approx $1500! I havent been able to find much online about the intake gaskets or how much they should cost to replace. Not sure if I just bite the bullet on this one. I'm kind of worried about paying the cost for this and then discovering something else is causing the CEL.
Btw, the car is totally stock aside from an axleback.