DIESEL5

hello, so yesterday my check engine light come on again, and the codes are the same that las time, i will like to know ideas and what to look for and what may cause that, the CODES are "Catalyst system Efficiency Below Threshold malfunctioning or defective catalyst system" and CODE 90 P1456 (90) EVAP Emission Control System Leak Detected (Fuel Tank System),
P1457 (90) EVAP Emission Control System Leak Detected (Control Canister System).SO ANY IDEAS AND WHAT CAN I DO TO FIX IT?????? Thank you for all the help.

all-mtr-teg

What year make and model?

DIESEL5

ACURA INTEGRA GS-R 2001

DIESEL5

ANYTHING??

95skunkedgsr

sounds like your o2 sensor is bad and the second one i dont know what that is it could be your gas cap not tightend all the way or something i would have to look it up further but the firs ones are deff o2 sensors

DIESEL5

so you think is the o2 sensor? is not the cat??

95skunkedgsr

well i mean it could be the cat the car is about 9 years old ... but i would just get a high flow cat new o2 sensor and reset the ecu and see if it comes back

95skunkedgsr

take the car to a advanced auto or what ever you have there and let them scan it with the scan tool and he will tell you what you need to replace/ upgrade

95skunkedgsr

my odb2 civic was throwing the cat code had them clear it and it never came back , might get lucky

DIESEL5

yes i guess i can have them clear it, but why the same codes came on like 2 months ago and then they went away after like two weeks and now the check engine light is on again with the same codes so that means i have the problem?? or is i clear the codes is different??

manoloek9

i had the same code on my ek just change the gas cap

DIESEL5

so you think changing the gas cap will fix the problem??

non-VTEC

the code p0420 for the cat usually means exactly that......the cat is no good. you need to replace it....BUT there is a reason the cat failed. in a perfect world it's supposed to last the life of the vehicle. but in realitly you are driving a 9+ year old honda that probably burns oil which caused the converter failure in the first place.

putting on a new one will work for a while but the code will come back. and putting a "high flow" cat wont work for very long either.

as for the evap leak code....check to see none of the lines are dissconected under the hood. check to see there is no rust around the fuel filler neck and check the condition of the gas cap seal. if any of those issues are there the code will keep coming back. you can replace the cap and make sure the filler neck is free of rust or corossion.

good luck

DIESEL5

thank you NON-VTEC good answers, but if the cat is bad, you said that means the car is burning oil or something is going on, buy i dont think thats the problem because the car doesnt smoke or anything and is running great, other think they say is that when the cat is bad that smells bad when the car is running and i havent smell anything, now about the evap leak im gonna try what you say,i hope thats the problem.

Relic1

actually 95% of the time the P0420 code is thrown for a failing secondary O2. (or wiring after a swap) Honda cats seldom fail unless you're doing something stupid with the fueling or seriously abusing the engine. Especially at only 9 years old. I had the stock cat in my hatch for 195k miles and after 15+ years of service it still barely registered on the emissions check for pollutants. You said no smoke and it doesn't burn oil, that's a very good sign. Replace the secondary O2.

as far as the evap code, non-VTEC hit it right on the head. But also keep in mind that if you drove with the cap loose once and have since tightened it, the codes will still be stored in the ECU.

DIESEL5

((((((actually 95% of the time the P0420 code is thrown for a failing secondary O2. (or wiring after a swap) Honda cats seldom fail unless you're doing something stupid with the fueling or seriously abusing the engine. Especially at only 9 years old. I had the stock cat in my hatch for 195k miles and after 15+ years of service it still barely registered on the emissions check for pollutants. You said no smoke and it doesn't burn oil, that's a very good sign. Replace the secondary O2.)))))))))

OK SO YOU THINK I SHOULD CHANGE THE O2 SENSOR FIRST?? IS AND GSR 2001 SO I HAS TWO O2 SENSORS,ONE BEFORE THE CAT AND ONE AFTER) BECAUSE WHEN I FIRST GOT THE CAR I CHANGE ONE OF THE O2 SENSORS SO MAYBE IS THE OTHER ONE NOW. (IS ANY WAY I CAN FIND OUT EXACLY WHATS THE PROBLEM?? OR I SHOULD JUST CHANGE THE O2 SENSOR ANYWAY??

((((((as far as the evap code, non-VTEC hit it right on the head. But also keep in mind that if you drove with the cap loose once and have since tightened it, the codes will still be stored in the ECU.)))))))

AND ABOUT THE EVAP CODE, SHOULD I RESET THE COMPU FIRST BEFORE I DO ANYTHING???AND WHATS THE BEST WAY TO RESET THE COMPU??

AND THANK YOU ALL YOU GUYS FOR YOUR GREAT ANSWER AND GREAT HELP, IT MAKES THIS JOB SO MUCH EASIER AND MORE FUN LOL. IS GREAT TO GET SOME HELP FROM PEOPLE WITH A LOT EXPERIENCE.

Relic1

Power spikes from a jump start or faulty connection can set all sorts of codes that do not actually exist. So the first step is always to clear the codes and see if they come back.
To clear the codes simply pull the negative battery terminal for 30 seconds (if you have an amp or something similer flip on the headlights to drain the caps) If you don't want to reset the settings in your radio pull the ECU for 30 seconds or have the person who read the codes clear them with their scan tool.

when the cat codes comes back after a few days of driving (or less) replace the secondary O2. Typically the primary O2 goes bad 6mo-1yr before the secondary.


BTW, some forum advice, caps are for abreviations and shouting only. If you want to quote someone else use the tags [ q u o t e ] before the quoted post and [ / q u o t e ] after to make it obvious what your post states. (spaces used to display the tags or the forum would think I'm quoting again)

DIESEL5

[QUOTE=Relic1;43192858]Power spikes from a jump start or faulty connection can set all sorts of codes that do not actually exist. So the first step is always to clear the codes and see if they come back.
To clear the codes simply pull the negative battery terminal for 30 seconds (if you have an amp or something similer flip on the headlights to drain the caps) If you don't want to reset the settings in your radio pull the ECU for 30 seconds or have the person who read the codes clear them with their scan tool.

when the cat codes comes back after a few days of driving (or less) replace the secondary O2. Typically the primary O2 goes bad 6mo-1yr before the secondary.


SO, IM GONNA RESET THE ECU TODAY AND SEE WHAT HAPPEND, SO YOU SAY THAT IS THE O2 SENSOR, THE ONE AFTER THE CAT RIGHT?? SO YOU YOU THINK I SHOULD WORRY ABOUT THE CAT??

Relic1

primary = pre-cat
secondary - post-cat
yes after the cat.

I would keep it in mind, but it wouldn't be at the top of my list.
One thing I forgot to ask, this is a stock cat correct? not one of those high flow ones that are basically a resonator with a little cat material on the outside edges.

DIESEL5

YES IS A STOCK CAT, I WAS PLANNING ON GETTING THE HIGH FLOW CAT,IS THAT A GOOD IDEA YOU THINK?

DIESEL5

QUOTE:::::hey my car did that ur getin code cuz either u have a bad cat or like just my problem was ur car has a cali ecu which means u have to get a cat that is for california emissions thats wat happn to me i put a reg highflow cat on and got that u can get rid of ithe code if u can find an ecu thats has not com out of a california car remember somtimes one code can trigger other codes even thou there may be nothing wrong with it besides the one code.is ur car from california ???
THIS IS OTHER POST SOMEONE TOLD ME, WHAT YOU THINK ABOUT THIS ONE?

Relic1

Civic OBD2 ECUs had cali-spec versions, but tegs did not.
(denoted by a L in the part number - 37820-xxx-Lxx)
I setup a cali-spec OBD2 civic ECU with a non cali-spec cat and it passed IL emissions sniffer test with no problem. (back when the testing was more than just a plug-and-play test)
The poster of that must have had something that was almost in need of replacement or something else that was causing problems.

DIESEL5

ok, thank you for askin me my question, ok so im gonna listen to you and im gonna replace the secondary O2 sensor

DIESEL5

so if i get aftermarket full cat back with the stock cat will be ok with the ecu??? no check engine lights??