Showing code P0420 for the last 4 months.

Asked by Apr 09, 2017 at 06:01 PM about the 2010 Honda Accord LX

Question type: Maintenance & Repair

Engine light was on. Showing P0420 (since 4 months). Dealership quote was
too expensive, they said catalytic converter needs replacement. Engine light
disappears/appears frequently. Don't have too much money to spend.
Please let me know how to proceed on this issue to minimize expenses. Is is
due to O2 sensors, or a choked and defective catalytic converter?

1 Answer

87,295

You should go to a independent exhaust shop if the catalytic converter needs replacement. After market cats are much cheaper than the OEM. Plus their labor rates would be lower than the dealer. The P0420 code means that the vehicle's control module has detected that the three-way catalytic converter is not working properly (is not as efficient as the factory is expecting). Replacing the oxygen (O2) sensors may sometimes fix the code, but in most cases the catalytic convert needs to be replaced to fix the problem. If the P0420 code is combined with other codes, try fixing the other codes first.

Your Answer:

Honda Accord Experts

  • #1
    JP1956
    Reputation
    2,290
  • #2
    Jonathan Ford
    Reputation
    1,750
  • #3
    dandyoun
    Reputation
    1,720
View All

Related Models For Sale

Used Toyota Camry
1,011 Great Deals out of 70,933 listings starting at $1,137
Used Honda Civic
529 Great Deals out of 40,610 listings starting at $1,615
Used Nissan Altima
925 Great Deals out of 54,566 listings starting at $1,300
Used Honda Accord Coupe
111 Great Deals out of 3,841 listings starting at $500
Used Toyota Corolla
695 Great Deals out of 60,527 listings starting at $1,400
Used Nissan Maxima
293 Great Deals out of 17,134 listings starting at $1,295
Used Honda CR-V
939 Great Deals out of 72,678 listings starting at $900
Used Acura TL
89 Great Deals out of 3,486 listings starting at $2,000
Used Hyundai Sonata
562 Great Deals out of 47,072 listings starting at $1,500
Used Kia Optima
344 Great Deals out of 28,032 listings starting at $1,000
Used Chevrolet Malibu
631 Great Deals out of 53,611 listings starting at $1,300
Used BMW 3 Series
954 Great Deals out of 29,852 listings starting at $950
Used Toyota Avalon
164 Great Deals out of 11,779 listings starting at $700
Used Dodge Charger
432 Great Deals out of 32,053 listings starting at $1,900

Used Cars For Sale

2016 Honda Accord LX For Sale
14 Great Deals out of 915 listings starting at $11,500
2015 Honda Accord LX For Sale
43 Great Deals out of 2,523 listings starting at $8,995
2014 Honda Accord LX For Sale
4 Great Deals out of 547 listings starting at $7,499

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.