How do I repair my 1999 Honda accord showing a check engine code of P0420

Question

I have replaced the fuel pump, and ox sensor.
The car will loose all power as if it is getting no fuel. When I stamp on the accelerator it regains power.

Answer 1

HI there

This code is for the bank 1 catalytic converter. If you have the 4 cylinder engine then you only have one bank. Sometimes the rear O2 sensor can cause this code as well as an exhaust leak. In most cases converter replacement is required however. If your converter is partially blocked this could be causing the problem. Here is a list of some other possible causes.

P0420 HONDA - Catalyst System Efficiency Below Threshold Bank 1

Read more: https://www.autocodes.com/p0420_honda.html