P0420 code

PALERO

MEMBER
2002 HONDA CRV
4 CYL
4WD
AUTOMATIC
109,000 MILES

What sensor do I have to replace with p0420 code my car

Wednesday, February 16th, 2011 AT 12:19 AM

5 Replies

RASMATAZ

MECHANIC
75,992 POSTS

Hello,

This code Catalyst System Efficiency Below Threshold (Bank 1) is because the catalytic converter is worn out here is a guide to help walk you through the replacement with diagrams below to help you with your car.

https://www.2carpros.com/articles/catalytic-converter-replacement

Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed.

Image (Click to make bigger)

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

-1

Wednesday, February 16th, 2011 AT 12:27 AM

JOEY LITTLE

MEMBER
1 POST
1999 HONDA CRV
4 CYL
AWD
AUTOMATIC
150,000 MILES

I have a code p0420 that says catalyst efficiency below threshold(bank 1). What is this?

Was this

answer

helpful?

Yes

No

Wednesday, February 13th, 2019 AT 8:10 PM (Merged)

BLUELIGHTNIN6

MECHANIC
16,542 POSTS

Usually a faulty O2 sensor will throw this code. Need to check your oxygen sensors. Follow the link below to learn how to test an oxygen sensor.

https://www.2carpros.com/how_to/how_to_test_oxygen_sensor.htm

If sensors are OK, need to flow test the catalytic converter..

Thanks for using 2CarPros.com!

Was this

answer

helpful?

Yes

No

+1

Wednesday, February 13th, 2019 AT 8:10 PM (Merged)

EGUZMAN72

MEMBER
1 POST
1999 HONDA CRV
4 CYL
4WD
AUTOMATIC
180,000 MILES

What does this code mean? I think it needs a regular maintenance but I am not sure.

Was this

answer

helpful?

Yes

No

Wednesday, February 13th, 2019 AT 8:10 PM (Merged)

KHLOW2008

MECHANIC
41,815 POSTS

Hi eguzman72,

P0420 = Catalyst efficiency below threshhold.

Usually this means the catalytic converter is bad. It is not a regular maintenance item.