2 trouble codes

2004 BMW 330CI
100,000 MILES • 6 CYL • FWD • AUTOMATIC
Avatar
RUDY9042
  • MEMBER
  • 1 POST
I have a 2004 BMW 330i car with 2 trouble codes: P0171 & P0172 = Bank 1 & 2 too lean.
What does this mean? How would it be repaired?
I thought it might be related to spark plugs because of a slight rough idle so I did an oil/filter change and replaced the spark plugs but rough idle still continues.
Dec 26, 2010 at 12:23 AM
Advertisement
Avatar
DOCHAGERTY
  • ASE Certified Mechanic
  • 9,606 POSTS
  • ASE Certified Mechanic
Inspect the intake boot from the air mass sensor to the throttle body, the boot often gets old and it can have tears in it, go to Realoem.com and look for part number 13541438759
Jan 10, 2011 at 10:37 PM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.