I have a 08 1500 with 4.8 and keep having the engine light come on. I have replaced bank 1, sensor 1 twice and then moved it to bank 2 and I still get P1133. I had it in the shop and no lean/ rich problems were found nor were any vacuum leaks found. Has anyone had this issue and any possible fixes??

 

I am having the same problem with my 08 1500 with a 5.3. Not sure what the cause is.