Ok heres my story:

Back in OCT 06, my engine light came on and showed Engine Error Code PO401-EGR Insufficient Flow Detected
. After months of trying to figure out how to fix the problem ( as showed in this thread -> https://www.honda-acura.net/forums/s...d.php?t=252827), I finally got my EGR Valve Ports cleaned in FEB 07 and that solved the problem.

Now, its March 08 and just recently my engine light came back on. I didnt pull the codes at first, because I figured it might be the EGR Valve again and just swapped out my old EGR Valve with a used one I bought from a 97 prelude. It seemed to work fine for a week with no engine light, but just yesterday it came back on. So I took it to my local Sears to have the engine codes pulled and they showed P0420-Catalyst System Efficiency Below Threshold.

Engine Error Codes List - http://www.troublecodes.net/honda/hondaobd2.shtml

Now a few questions:
1. Will the EGR Valve affect this code? Because it seemed to work fine for a week when i did change it out.
2. If not, then what else do I need to do in order to get this problem resolved?


Thanks for any help.