1998 Honda Accord 4 cyl
Failed emissions with the following OBD Trouble Codes:

P0420 Catalyst System Efficiency Below Threshold (Bank1)
P0401 Exhaust Gas Recirculation Flow Insufficient Detected
P1457 (no description but I have been told it is an EVAP leak?)

My wife lost gas cap 3 years ago and has driven the car for 50 miles. I bought the original gas cap after few days in Honda Dealership and week after I got engine light on. I had engine light on for the last 3 years and always passed emission test except this year because now test check computer as well.

Please help.

 

I've had that P0420 code and it seems like everyone gets it at some point in an Accord's life.

Here is a post I did awhile back on it, basically I looked for leaks, looked at O2 sensor and the catalytic converter (it ended up being a combination of all 3 but an easy fix).

This should address the P0420 code and usually the other two will hopefully clear out as well.

Here is the link to the post

https://www.hondaaccordforum.com/for...de-pics-50458/

 

Thank you mamtsberg I will try.