he guys, my check engine light came on on Last week so I brought it to my friends house to get my engine scanned and the P0420 code was the diagnosis. my friend cleared the code and has not reappeared since and have driven roughly 300 miles. am I okay to keep driving until code reappears or am I causing significant damage without me realizing??? thanks so much for your help in advance!!!

 

It's OK to drive. Code may return at some point. I had this code on Subaru Forester and it would sometimes go months before returning. After replacing the converter, code did not return for 1.5 yrs, then returned.

good luck

 

thanks for your feedback

 

I know this is old but I was having the same problem - P0420 would come - stay on for a week or two then go off for a few weeks. Cycled like that for a while before I put a treatment of techron in the fuel talk. A week later the light was gone and hasn't come back. I drop a bottle of Techron into the fuel tank every 6 months or so now just to try to keep the error away. 125K miles on my 2006 TSX.

 

thanks for post. Good to know that Techron might be a fix for P0420. This implies ability of Techron to clean catalytic converter, something many have tried w/o success. Check youtube for examples by ericthecarguy.

good luck