Help! C.Converter/o2 issues

[Ace4x4]

Hey, new to the forum, been doing research. Need some advice. My wife has an 03 Chevy Tahoe 5.3L V8 4x4.

She has had the check engine light on for almost a year now, I never really drove it, she said it just got tripped from a flood we had, I believed her... Anyways I decided to take it to autozone get a diagnostic ran. It showed the code P0135, bad o2 sensor bank1 sensor1. I bought an o2 sensor that was match for her truck, not the universal. I replaced the sensor, left the batt. unplugged for about an hour. Turned it on, the idle problem went away, light remained for about 15 minutes of driving, went off. problem solved. Hah yeah, right.

She calls me this morning, check engine light is back on and she hears a feint metal crackling like sound when she applies her gas. She brought me the truck, i got down and burned the eff out of myself making sure the o2 sensor was firm in place. It was going nowhere. I told her to swing by get the codes checked. It spit out another P0135 -B1 S1. This time though it also ran the P0420 - Catalyst Efficiency low bank1.... So just to be sure everything was still right with the 02, i got under there (what a pain in the rear job to get to that harness) I removed the o2 sensor from pipe and plug. Reattach everything nice and firm. Let the battery chill for 15 minutes. Start it back up, still have that very hard to hear but very much there metal crackling sound.

Sorry this is such a long post... So now from everything i have read, cats go bad, the truck is up to 172k miles but she is mother of 2 drives responsible very on the ball with maintenance never had any serious problems. Is that sound the cat breaking up? Whats the best thing to do, she seems to think i miffed the job... I have done some much more intense work on trucks then just an o2 sensor. So she is ready to go mechanic route. I don't want to pay for anything we don't need, but i know jack about Cat.Cons.

Also whats the danger of running the truck for another week or so as we look into repairs? I have noticed a slight loss of power but it was running fine right after i replaced the o2 the first time around.
Any help would be greatly appreciated.

Thanks for your time guys.

 

[chip]

I've had the P0430 code for a while now. I almost replaced my O2 sensors, but I'm going to try this first: http://www.cataclean.com/

I assume it's the cat you're hearing.

 

[afpj]

Did you just try gently tapping on the cats to see if they/it rattles? I read that somewhere on this forum. Just throwing out simple stuff just in case. Good luck.

 

[chip]

Did you just try gently tapping on the cats to see if they/it rattles? I read that somewhere on this forum. Just throwing out simple stuff just in case. Good luck.

Good idea! Thanks.

 

[bigbird189]

I've had the P0430 code for a while now. I almost replaced my O2 sensors, but I'm going to try this first: http://www.cataclean.com/

I assume it's the cat you're hearing.

I was wondering if the cataclean worked for you? I having the same problem and have replaced the bank 1 sensor and put a new air filter and still check engine light on.

 

[chip]

I was wondering if the cataclean worked for you? I having the same problem and have replaced the bank 1 sensor and put a new air filter and still check engine light on.

The Cataclean did not solve the check engine light. The next thing I tried was the downstream O2 sensor (Bank 2 - Passenger Side). That worked. No problems since.

 

[animalfries]

The Cataclean did not solve the check engine light. The next thing I tried was the downstream O2 sensor (Bank 2 - Passenger Side). That worked. No problems since.

Chip, can you confirm that you had a CAT code and not an 02 code, but you replaced the 02 and it erased the CAT code?

I have the same code saying a Cat is bad and I'm about to buy a new cat. A new 02 sensor is much cheaper than even a universal cat!

 

[chip]

Chip, can you confirm that you had a CAT code and not an 02 code, but you replaced the 02 and it erased the CAT code?

I have the same code saying a Cat is bad and I'm about to buy a new cat. A new 02 sensor is much cheaper than even a universal cat!

I had somthing like: "P0430 - Catalyst efficiency threshold low: Bank 2."

I created a thread for it, if you feel like searching. It might have some more info. Many codes have multiple possibilities (this one included).