I have a '03 Acura RSX with about 170K miles. After the P-140 code (or the oxygen sensor issue code) I replaced the front O2 sensor and the check engine light remained on. I used an anti foul spark plug insert and the code light stayed off for about 25K miles. After I loaned the car to my lead-foot son, he returned the car with the 02 code again. I reset the code and the check engine light stayed off for about 100 miles. Should I try a shield on the back sensor? Any ideas on how to get the code to stay off?

Thanks

 

https://acurazine.com/forums/

look here ^^^

 

Perhaps there is an issue with the rear 02 sensor, or maybe a clogged cat?

 

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