Hi all. Need help here. I have an 03 xtype 2.5. Was having cylinder misfire on cylinder 5. So i replaced all plugs and the needed coil.car continued to have multiple misfires so i then replaced all 6 coils. Now the car seems to run smoother. But whe the car is cold keep in mind i live in upstate NY and it is October, i am getting multiple misfires and getting p0104 and p0171 both banks too lean. I have looked for air leaks but cannot seem to find any anywhere! I have read almost every post possible and need help. I also have some trouble at times with the breaks acting real funky so i double checked the brake booster and valve but it seems to be ok. What am i doing wrong here? Any help would be great! Thanks.

 

Check what the fuel trims do - there are a bazillion posts about this.