So I'm asking for a friend who doesn't have access to internet. His only vehicle is an 04 Quad Cab 4.7 with about 220,000 miles and he's had a P0420 code for awhile but he use to get a P0305 too but now instead he's getting a P0301. He hasn't switched anything around. The converter is a y-pipe assembly so he's doesn't have funds to purchase the converter right now. He's doesn't need inspection anymore so he said he tried to drill a hole through the converters. After doing that he said the P0301 and P0157 codes came up of course along with the P0420. Then he said he tried to put some steel putty back over the holes. I did give him my old Cen-Tech Harbor Freight tool scanner that gives some access to live data. He says the Bank 2 Sensor 2 live data shows 0 at idle and then jumps up when you press the gas in or drive. Is that correct? I remember the O2 sensor data range on my Ford you could tell if the engine was adding too much fuel. I can't remember what the numbers would be if it was adding too much fuel or taking it away? What's the range he should be seeing on the O2 sensors data? He said it has 4. We did original plugs last summer and they weren't oily or anything. We also changed that number 5 coil when he first had the P0305. We also did a new fuel pump assembly last year when he was having a constant power loss. Pressure was only at 25PSI. That was before doing the plugs.