P0172, P0175, & P0430

[jryerson]

What are other causes other than O2 sensor that would throw these codes? I was told that the O2 sensors were bad and causing these codes. I replaced the O2 sensors and the "SES" light came back on. I haven't had the codes read but I can only imagine that they are the same.

[builderpaul]

system too rich bank one and system too rich bank 2. The last code is for catalyst below threshold bank 2.

Lots of reasons for rich condition. Run a fuel pressure bleed down test to see if your regulator is leaking. Have the injectors cleaned. Test the output of the IAT sensor, coolent temp sensor. Just curious why did you replace the O2 sensors.

Fix the first 2 codes. The last code could be caused by the too rich conditon.

[Black02Silverado]

Mine was getting this code every so often. It would clear up after 20 miles of driving. I switched gas stations and never seen the code again. Guess it was bad gas.