P0430 for 1999 Chevy Suburban

OK. I have a 1999 Chevy Suburban that has 157 miles on it. I recently got the catalytic converters, o2 sensors and fuel pump changed out on it. When all was seeming all too well the check engine light came on with the code P0430. Can anyone shed some light as to what this could possibly mean? Thanks in advance

1999 with only 157 miles. Cool. (just funnin’)

The code means “catalyst system efficiency below threshold”.

Normally it would mean either the catalyst has been compromised due to exhaust stream deposits onto the platinum palldium over time (cat connverter shot) or the downstream oxygen sensor(s) is defective.

Which O2 sensors were changed? Both upstream and downstream?
Why was the work done?

And, since you had it done rather than doing it yourself, have you brought it back to the shop to look at?

Normally what I’d want to do is look at the signals from the oxygen sensors themselves.

My friend’s husband did the work, because my husband was deployed. I had it changed, because I was having problems with the drivability then and 2 places I took it to swore up and down that the catalytic converters were bad. After they were replaced, the problem didn’t go away and so we changed out all the O2 sensors and then finally the pump. All along the problem was the fuel pressure sensor. All this was done back in January.

Could there be something wrong somewhere else that would cause the O2s or the Cats to go bad?

I think you have been using one of those “see-code-change-part” shops. These shops/mechanics don’t do any troubleshooting, just change parts to remove the symptoms. These sorry shops/mechanics give good shops/mechanics a tainted name by being in the same profession.
You might try some arm twisting on this shop, to get the job done right, which performed this disservice for you; or, you could try to find a shop with competent, honest, mechanics to find the causes of the symptoms, and repair those causes..

Two sorry shops took you down the wrong road. Unfortunately, those types of shops/mechanics are far too many.
The code P0430 is for out of range voltage values of sensor signals in the catalytic converter system, bank 2. This is on the other side of the engine from bank 1 (which has #1 spark plug, and would have code P0420 if there were a problem indicated in that circuit).
This is the type of troubleshooting checklist a good mechanic follows for Codes P0420, and P0430 (and, s/he doesn’t pretend to follow such a checklist): http://www.obd-codes.com/p0420

My sincerest thanks to your husband for serving our country and to you for your sacrifice while he does so.

Unless the engine is having severe problems, like burning oil by the barrel, there’s nothing that would make it go bad immediately like this. The only real thing that kills cat converters and oxygen sensors quickly is if the surfaces get coated. It’s the surface contact with the exhaust stream by which they do their jobs.

It is possible the incorrect oxygen sensors were used. Your husband’s friend would not be the first to make this mistake. Perhaps a shop with a scope can look at the traces.

Guys, any other thoughts? I could use some help here. We’re helping a military family. She deserves our best…not just my rambling thoughts.