P0171 code

2000 TOYOTA AVALON
140,000 MILES • 3.0L • V6 • FWD • AUTOMATIC
Avatar
ALZACK41
  • MEMBER
  • 20 POSTS
B1S1 and B2S1, just replaced with Toyota Genuine Air/Fuel sensor.

P0171 code still came on after three hours driving.

Can old downstream Oxygen sensor trigger that code, and should I also renew it?
Jan 19, 2017 at 8:31 PM
Advertisement
Avatar
SATURNTECH9
  • ✓Experienced Mechanic
  • 30,869 POSTS
I would be looking for a vacuum leak before changing a o2 sensor that is usually what sets lean codes.
Jan 19, 2017 at 10:58 PM
Avatar
SATURNTECH9
  • ✓Experienced Mechanic
  • 30,869 POSTS
Also, down stream o2 sensor just helps check the health of the catalytic converter.
Jan 19, 2017 at 10:59 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.