Just bought this car and its pretty damn nice. New paint(done right), everything works flawlessly. 99' LX w 119k for $3200 guy wanted 4k. Cash talks lol.

Did my homework before buying and have found out that the CG transmissions (auto) are crappy. But it was between the 2001 mazda millenias, and the 02-03 maximas, and 98-02 accord, and i chose the accord over them for the reliabilty factor, low maintenance costs, and aftermarket support.

Now i have a few questions...i have scanned the "CEL" Sticky and found out my three codes to be:

P0420 67 Catalyst System Efficiency Below Threshold.

P0401 80 EGR Insufficient Flow Detected - this code showed twice on scanner.

Code one is a oxygen sensor possibly or a bad catalytic converter?

The second code possibly bad sensor? Is there egr ports to clean?*

Any info is all very appreciated. Thanks in advance.

 

4 or 6 cyl?
o2 sensors could be excessively dirty from running with clogged egr ports.
clean the ports.
unfortunately for the p0420 the previous owner may have damaged the cat as well with the neglected egr cleaning, tune up etc.. hope this helps.

 

its a 4cyl.

Yeah ive been looking into the EGR Cleaning DIY on 6thgenaccord.com and what ive searched here on HT, ill be doing this here as soon as i get a chance. I have a Hesitation sometimes while driving and im pretty sure thats the culprit.

Now onto the P0420 67 Catalyst System Efficiency Below Threshold. Im thinking a new cat/02 sensor is the right fix.

With that being said im a "Test-Pipe" guy...ran em on all my obd1 hondas. Locally we have no emissions testing at all in metro Jacksonville, FL.

I am looking at the "Megan Racing" Test-Pipe (on ebay) to swap out my Cat with....im going to buy a new O2 sensor as well from "Rock Auto".

I read a concerning post about "Cat deletes" - "Test-Pipes" - "High-Flow Cats" and was a litttle skeptical of buying a test-pipe, because im trying to remove my "CEL"... and i read claims people spoke of still having a "CEL" after installtion of a "Test-Pipe".

has anyone on here experienced "CEL's" after installtion of a "Test-Pipe" on a ob2 system?

 

a test pipe will throw a cel if obd2.
to get rid of the cel do what you mentioned first. inspect o2 sensors and cat. and a lot of other threads with this issue end with a new cat.
don't buy anything until you figured out the actual problem.
the secondary o2 sensor is sensing the same as the primary sensor thus making the ecu think that no cat is present.