Live Data
Last reported case: 2 weeks ago
Based on 10 owner reports (3 from Reddit, 7 from forums)
What is P0420?
🚗P0420 on 2010 HONDA Accord
This page focuses specifically on P0420 issues reported by 2010 HONDA Accord owners. The experiences and fixes below are from real owners of this exact vehicle.
Symptoms Reported by 2010 HONDA Accord Owners:
rough idleheadachecheck engine lightwatery eyes
Parts Often Involved:
downstream sensorbatteryharmonic balancercatalytic converterheater bloweroxygen sensormufflercamshaftcel lightradio
What Owners Say
Real experiences from 2010 HONDA Accord owners
Cost Reportvia reddit_post
“I initially bought for $2,500 in 2022. Radio is disconnected because there was an electrical short that kept draining and killing the battery. (Yes, even when the radio was turned off.”View original
Experiencevia reddit_post
“Many of the people on this page were very nice and insightful when I’ve posted on here in the past. A little less than a month ago, I had to get my transmission solenoid replaced on my car.”View original
Experiencevia reddit_post
“Just bought a used 2009 Honda accord with a 3.5L V6. The dealer recommended that I use premium gas in it - there is a p0420 code so he said the "premium gas" was taking care of it.”View original
Experiencevia reddit_post
“The dealer recommended that I use premium gas in it - there is a p0420 code so he said the "premium gas" was taking care of it. I have a feeling he's full of shit lol.”View original
Cost Reportvia forum_post
“p0420 & $600 Bucks later Hey Guys, I have an issue witha 2003 Honda Accord 2.4, with 285,000 kms on it I had the CEL light come on as well as some type of fumes coming into the car when the heater blower was turned on.”View original
Fixed Itvia forum_post
“This often points to a failing catalytic converter, but other issues like oxygen sensor problems, exhaust leaks, or even fuel system problems can also trigger the code) I didn’t notice any problems with the vehicle, it was driving smooth with what seemed to be decent gas milage, no lose of power, so I cleared the code to see if it would come back on.. 6 days later the same light and code pops up, but also with another light VSA (vehicle stability) light + another code p0341.”View original
Experiencevia forum_post
“It's throwing the P0420 code and I understand what it is referencing the CAT but there's a lot of different possible fixes. Attached is the freeze frame data.”View original
Experiencevia forum_post
“This is all over the last 2 weeks. But Over the last few days I noticed my car losing power and is having a hard time getting up any type of hill so I’ve stopped driving the car.”View original
Experiencevia forum_post
“I could replace the converter but that will be a matter of time until it goes bad again. I’ve been looking at other threads but don’t know of a good way to approach the problem.”View original
Experiencevia forum_post
“Also anyone have an idea about the fumes coming into the car if there is no leak on the exhaust or oil leaks on the car, i did change the PCV valve. Thanks”View original
These are real experiences shared by 2010 HONDA Accord owners on automotive forums and communities. Results may vary based on vehicle condition and repair quality.
About This Data
This page aggregates 10 discussions about P0420 from 2010 HONDA Accord owners across automotive communities.
Success rate (20%) is calculated from posts where owners confirmed whether their fix resolved the issue.
Last updated: 1/5/2026