On a clog cat, why would it make the engine run lean?

2001 FORD ESCAPE
50,000 MILES • 6 CYL • 2WD • AUTOMATIC
Avatar
MIKELEE7772
  • MEMBER
  • 1 POST
ON a clog cat why would it make the engine on that bank run lean? For all three have miss fire cly, and make that bank run lean?
Dec 22, 2010 at 7:10 AM
Advertisement
Avatar
MHPAUTOS
  • ✓ASE Certified Mechanic
  • 31,937 POSTS
  • ASE Certified Mechanic
If anything it will run rich, may be the upstream O2 sensor is causing the ECU to lean it out due to a faulty signal, replace the bad cat and see what you get in the way of codes.

mark (mhpautos)
Dec 28, 2010 at 2:47 AM
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.