Check Engine Light Codes? Anyone have resources?

[1994]

I had a check engine light on in my 1999 Classic Silverado C1500, and I got someone with a code reader to plug it in and the following codes came up;

CO281

CO238

CO226

CO222

Anyone have a database where I could check these codes or does anyone know what they are? Thanks.

 

[shorepatrol]

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