1999 Other Ford Models Oxygen Sensors

1999 FORD
130,000 MILES • 4 CYL • FWD • MANUAL
Avatar
KIMBERLYCOY
  • MEMBER
  • 1 POST
I ran a diagnostic check on my car because the service engine light keeps coming on. I got the code p 1131 and looked it up online. I found that it was the O2 sensor. I called a parts store to price it and was told there are 2 on the car I have and my question is, which one of the 2 is it more common to go out. It is an Escort ZX2.

Thank you.
Apr 8, 2009 at 7:20 PM
Advertisement
Avatar
MHPAUTOS
  • ✓ASE Certified Mechanic
  • 31,937 POSTS
  • ASE Certified Mechanic
Hi there,

with 2 O2 sensors, the up stream sensor is the active unit, the down stream is for collaboration, you can check this by, clearing the codes and un plugging the rear sensor, and see if it set the same code.

Mark (mhpautos)
Apr 8, 2009 at 8:21 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.