Q: CE Light came on , got it checked and it said PO420. Couple of day later went off and has not come back on. 2011 Jeep Compass

asked by on December 28, 2016

My light came on and then went off and stayed off . Is my converter going bad or is it just a sensor ?

My car has 90000 miles.
My car has an automatic transmission.

Check Engine Light is on Inspection $79.99 - $89.99 Get a Quote

Hi there - yes, it is possible the catalytic converter has lost it’s ability to burn residual fuel. This could be due to an engine condition that has clogged the catalyst, or a failing oxygen sensor that is not adequately monitoring exhaust gases, and feeding bad data to engine management. The result is the same, inadequate catalytic converter functionality. I would recommend a Check Engine inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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