Help!!! Engine Code Questions ...P0420

[TomK]

Helpp.. I got engine light on and res it right now. It show P0420 which is Catalyst system eficiency below threshold. I changed the aftermaket catalyst a few days ago. Suddenly, the engine light on when I am driving. I am concern the light back on again. If it does, what can I do? Change the stock cataylst back? any solutions and suggestion please... ?
Thank you

 

[Matt.]

did you install a high flow cat?

 

[TomK]

yes I install high flow cat

 

[Matt.]

there you go

 

[whtcivic93]

there you go

i have a high flow cat on the DC2 with no CEL

 

[Matt.]

i have a high flow cat on the DC2 with no CEL

There was a rumor that some first gen obd2 honda vehicles actually ran like obd1, so you may not even need a secondary o2 sensor, which may be by this works.

 

[whtcivic93]

There was a rumor that some first gen obd2 honda vehicles actually ran like obd1, so you may not even need a secondary o2 sensor, which may be by this works.

I doubt a 99 is considered a "first gen OBD2 vehicle" considering OBD2 was a requirement by 1996. Im sure three years was plenty of time for honda to work the kinks out.

Unless youre referring to his 6th gen..

 

[Steven.]

there is OBD2A and OBD2B
all within 96-00

 

[whtcivic93]

there is OBD2A and OBD2B
all within 96-00

Hmm i knew that, i just dont know how to tell the difference... help me out lol

 

[Matt.]

96-98 obd2a 99-00 obd2b anything after that I have no clue

 

[Steven.]

96-98 obd2a 99-00 obd2b anything after that I have no clue

except HX civics

 

[killrhatch]

Test Pipe!!! who needs a cat? take it off..put a text pipe!! enjoy the extra couple hp!!! lol

 

[TomK]

obd2b?? what is it?

 

[Civic Stud]

yes I install high flow cat

Is it an actual high flow catalytic convertor or an ebay high flow cat (test pipe)? Can you see through it?

 

[Steven.]

http://www.kingmotorsports.com/category.aspx?cat=6

although yo ucna buy the same part for alot less at the auto parts store

 

[TomK]

yes.. I brought it from ebay it is just a pipe

 

[Steven.]

http://clubhondahawaii.proboards58.com/index.cgi?board=diygarage&action=display&thread=1123294890

 

[TomK]

Thank you all guys reply......

 

[Matt.]

except HX civics

huh?

 

[TomK]

Sorry. I live in Saskatoon, Canada. I cannot find Spark Plug Non Fouler from Canadian Tire, Parts and Source and ebay also. Where can I buy it online?