xhris said:
Ok, sorry to ressurect this thread, but i just got the same code 0420. Checked it out and the description is "catalyst system efficiency below threshold (Bank 1)"
I know mark said no problem, but im just double checking.
thx guys.
hay buddy, i have an 02 spec v and i keep getting an 0420 fault also. i know what it is also, on the fault. but i called nissan, they said forward o2 sensor, but it didn't fix it. so maybe the rear one.they just cost so much, i don't want to buy another o2 for nothing. but i have done a lot of mods to the car, header , exhaust, intake, i had to move the o2 sensors to accomodate the high flow cat. i'll let you know when i find out what it is. i was fine for 8 months after installing all the mods, so i know that's not it.in case you are wondering how to check your codes on the ecu without any help, here it is.
i don't know all the cars it works on , but it does an 02 spec v...
turn ignition switch to acc(lights on on dash)
wait exactly 3 seconds,
pump gas 5 times within 5 seconds
wait exactly 7 seconds
hold gas for 10 seconds
the service engine soon light(ses) will start blinking
ten is 0 1 is 1 2 is 2 and so on
there is a break between blinks and all codes are 4 digits
the code will repeat itself continually
hold the gas for ten second after the first set of numbers and the ecu will reset
i forgot the link, but the list of codes are out there on the internet
hope to get in touch with you soon. i can't figure it out either!! and my warranty is up. good luck.