PO420 code

[Deacon Sam]

Alright, be working on my Tahoe fixin afew things. Had multiple codes but slowly worked thru them & was code free since Sunday & was going to to get it inspected today, then BAM service engine light back on!!! What??? pull codes & now have PO420?? where should I start???

 

[BRUTUS_T_HOG]

Pretty likely it's a bad bank 1 catalytic converter. Rarely this code can be caused be o2 sensors or fuel system issue

 

[SunlitComet]

a chemically worn out cat for the left engine bank.

 

[Deacon Sam]

Sorry haven't gotten back on this but been busy at work and different things. Yes it says bank 1, was told it was the left O2 sensor by one mechanic. It only has one cat on it.

 

[Deacon Sam]

Alright was able to get under the Tahoe the other day found all 4 O2 sensors and 2 cats, was told only had one, go figure was supposed to be mechanic.
So, Sunlitcomet you saying it is definitely the left bank cat most likely, just replace it only?

 

[kcb37]

Yes cat.
Replace depends on how you do it. Will post a link to what I bought for my wifes 99.
You need to replace it to pass emissions so your stuck. For now I am waiting.
Reason being any oil, coolant, etc... will cause a cat to go bad.

If you feel like doing it get on youtube and search P0420 their are several videos about how to clean a cat. Weather this works or not I have no idea never tried.

To add if you have a scrap yard around you hold on to the cats, drop them when you are close. Not worth the gas to make a special trip but you should get atleast $15 a piece. Have them mail the check will be a 3 to 5 day wait. Something like that.

http://www.summitracing.com/parts/wlk-50410/overview/year/1999/make/chevrolet/model/tahoe

 

[Deacon Sam]

Thanks for the info, gonna order new y-pipe with both cats in the next few days.