Hello all,
I need someone's expertise. I have a 2002 a4 1.8t and the check engine light came on. I went to Autozone to get the code read and the code is P0170

Fuel Trim Malfunction (Bank 1) A

Theguy at autozonesaid it could be the o2 sensor, MAF, Coil pack. They said the car is running lean, I guess not enough gas. The car runs fine. No rough idle, no stalling. The car is stock, no mods and no power loss. I hope you all can help me. I usually do my own work on my cars and I don't have a problem working on the car. I don't have enough money to take it to a shop and I don't have any warranty on the vehicle. Your help will be much appreciated.
Thanks!

 

Did you put a K&N filter in?

I ask since a few days after I installed mine, I got that exact same code. A little while later, I had to replace my MAF. I'm using the stock air filter now.