Hello,

I have this Code from car got it from AutoZone. P0420- The PCM has determined that the catalyst system efficiency for bank 1 is below Threshold for the current engine opertaing conditions. Bank 1 identifies the location of cylinder #1. While Bank 2 identifies the cylinder on the opposite bank.


The guy from the store told me it most likey is an Oxygen Sensor. Our car has 2 and must be the top one that is out.


Does it anyone know how difficult it will be to change? and how long?

Also my Maint. light is starting to blink when I start the car but it does not stay on just blinks. I don't think it did that before.

I have done a search but some people change theirs Catalyst and I don't want to do that unlesss I need to. How can you tell if the Oxygen Sensor is no longer good?

Any help is greatly appreciated.

 

You need an ODBII scan tool that can give you live data reading from Both O2 Sensor while you are driving. you need someone who understan the data. The easiest way to understan the reading from the O2 is as follow the front O2 volt changes is more rapid then the one after the cat. The O2 after the CAT shoud have a more stady voltage reading.

I don't think is your O2 sensor, if you only get P0420 this means your CAT. If you O2 have problem you will get P0420 and something else. This is a know problem with ealier TL (usually 1999) and early Honda Accord V6 CAT. Acura fix the problem with 2000 and up TL, if you go to the dealer now they actually replace your cat with the 2000 and up model number. So replacing the O2 sensor will not fix your problem and you are wasting your money.

you can try using some fuel system cleaner. Clear the check engine light and run fuel systems cleaner 2 or 3 times see this resolved your problem.

If the problem comes back you need to replace your CAT, since you live in NYC you can go buy an aftermarket cat they are around $160 for the TL I think DEC makes them model HON1680 for cali emission car and HON1680A for fed emission car.
Or you can go OEM Acura but that will run you around $600.

Good luck let me know if you need help reading O2 I live in queens also.

~RW

 

well I can tell you about the maint. light, it is just letting you know that you car is soon due for scheduled maint. whats your mileage at now?

 

He asked about the Check Engine Light not the Maint Req light. Plus you wouldn't get codes from the Maint Req light.

 

he asked right there about the maint. light. he also said any help is appreciated. I knew about the maint. light so I helped. next time read the whole thread before you try to make me look dumb, cause in turn you just made your self look like a donkey.

 

 

I forgot to mention that. My odometer is at 105k I have done the full tune-up already. I also have had the light turned off either 2-3 time and comes back on after a day or two. So something is wrong for sure I believe. If it were the CAT where can I find it? Junkyard do you believe would be a good place? I don't want to buy it from the dealer that would mean some $$$.

RW- pdprich Can you help me get the more accurate reading? I am in Sunnyside how about you?

Thanks

 

I have about the same miles on my TL when I the got P0420 light I think my was at 97K when the my CAT have problems.

Go to www.convertergeek.com they have a DEC CAT for the TL I think is around $160 or $170 and free shipping.
It is illegal for junkyard to sell a used CAT unless is a recertified CAT, so is hard to located a Junkyard that will sell you a used CAT.

TLNY: sent me a private message, I live in Flushing.

 

there is no way to really look at your O2 sensors and say "ok this one is bad", because of all the heat they all look bad. if you change one you better change them all. its eaisier that way. not hard to do at all. i had the same problem and i ended changing the cat and all the O2 sensors. the check engine light went off after that.