code 0420

In the only post I have been able to find from a search. 0420 is said to be from a bad catalytic converter. Code 0420, Catalyst system effiency below threshold (Bank 1) is the explanation for this code. Do I need a new Converter. I am pretty sure I do but before I spend any more $ unnecessarily I want to hear from some more experienced persons on the subject. Thanks for your patience.

From http://www.chevymania.com/tech/obdii.htm

A very common code to get is P0420 or P0421.

These refer to the converter. Many times after testing these systems no issue can be found with the converters or the related HO2S sensor. This doesn't mean swap the converter or the sensor. If you have this code and you can't find any obvious problems (like a gutted/missing cat or missing or damaged sensor/wire) and the vehicle has no drivability problems, there may not be a problem!! I can already see the eyebrows going up!! There are a few reported cases where the software in the PCM has too narrow a range. These are usually noted in TSB's and typically can be performed at a local dealership at no cost to you. I can also hear 'but my warranty is out!' Most Catalysts systems have a Federally Mandated 8 year 80,000-mile warranty. This is a fact that the dealership doesn't want you to know but...if your vehicle has a P0420 or P0421 code before 80,000 miles or 8 years the dealership can be liable for replacement or repair. 99% of the time it takes a matter of minutes for this EEPROM FLASH and it turns off the MIL light immediately.

In one of my lrecent posts I explained a problem that the engine was missing excessively while driving and the other day it just quit running. I could not get it to start checked fuel filter and continued to try to start it and it would idle very rough for a few seconds then die. I had it towed to a mechanic and he found that the rotor in the distributor had lost a screw and arched inside the distributor and caused the shut down. While trying to start it, it chugged, backfired and then I heard what sounded to be somthing metalic pop, which I think was the converter. I only tell you this for clarity, hopping to give you a better understanding of the situation. Hope I did not make matters worse.

yip, sounds like the convertor.

Why did you not include this in your last thread and why did you start a whole new thread for the same truck.

Stick to ONE THREAD ONLY to stop confusion like this.

I find anymore and they will be locked.

This is a new problem entirely. I posted the last statement to let members know what the last problem was. I did not believe that making a post for a different problem seperate from a previous one would violate any rules. Am I permeited to make new posts to inquire about new problems? sorry for the error , and thanks for your help

it is still related to the same overall engine problem and does not warrant a new thread.

Keep it all in one thread or people will get confused and will walk.

Had it to the mechanic like I said it seems to be fine now. Had to replace the Cat conv. seems I blew it out when it was missfiring and not running properly. Just put the converter on yesterday, waiting to see what else goes wrong. Thanks to all for the help and appologies for not keeping all info on the same post.

No problem, glad to see things are better.

Reset the computer now so the computer can relearn the better fuel/ air ratio.