99 tahoe code problems

[MJH0815]

Hey guys. My 99 tahoe has been throwing P0420. I keep clearing it because I can't afford to replace the cat yet. But today it threw P0430 and not P0420. I know what both codes mean. My question is why would it jump for one bank to the next and not include both? I've replaced both O2 sensors. It does this once in a while? Any ideas of why it jumps?

 

[lesterl]

I would get some live data, CEL codes mean little more than "something aint right"....

 

[MJH0815]

Thanks man. I'll give that a shot

 

[kebler95]

I have question concerning the p0420 Code. I am aware of what it is trying to say to me about the CAT Converter, and the o2 Sens.
My question, is since I have not personally had to check and change this out myself. What are the steps i should take to asset the issue and what are some of the best types to use as far as if I need to replace one of them or both.
I was also wandering if it matter what kinda CAT Convert I use.
I live in Dallas, I own a 1999 Chevy Tahoe, 2WB Four Door,. I have recently replaced the Fuel Pump and Coil on it within the last month.
If you can give me a few tips or step by step guid, I would appricate it VERY Much thanks !!

 

[MJH0815]

I would start with your O2 sensor. That's where I started. Then if it keeps acting up I'd try some cataclean from mister gasket. I used it in my 99 4wd 4dr and it seemed to work and is much cheaper then replacing the cat. That's where I would start

 

[MJH0815]

As far as brands of O2 sensers I used boch

 

[kebler95]

Ok thanks a bunch for that tip I wouldn't of know about the catacleaner.

 

[MJH0815]

Neither did i. I checked it out on YouTube and figured it was worth a shot.

 

[lesterl]

I avoid Bosch anything on GM if I can.

Live data of sensor 1 & 2 would be helpful both banks

 

[kebler95]

I just changed out bank 1 today . I did use bosh, sorry . Figure it would be best. So let's see what happens within the next Couple days if the light doesn't or does come back on . Thanks for the advice though guys helps out a lot

 

[lesterl]

NP, I've just had bad luck with bosch.. plugs primarily....