Foxtrot06

I'm not the one that did the testing just relaying what I was told. Wouldn't a clogged cat cause this issue from start up not after running for awhile?

5.3L. No new codes from what I remember. Original codes were p0300 I believe. Unfortunately I don't currently have quick access to the truck to check.

I have a 03 Silverado that starts up and runs fine but after awhile it starts dropping cylinders on one bank, like it was leaning out one bank, it then proceeds to stall. O2 Sensors have been replaced, fuel pressure is good, plugs and coil packs are good.