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

2001 FORD ESCAPE
50,000 MILES • 6 CYL • 2WD • AUTOMATIC
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MIKELEE7772
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  • 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 21, 2010 at 11:10 PM
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MHPAUTOS
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  • 31,937 POSTS
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 27, 2010 at 6:47 PM
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