Don’t recall ever seeing this previously on my 2006 Denali but live data yesterday, reveals 99.2% at S2 both banks. Have had P0430 pointing to CAT on bank 2. Long and sort term trims otherwise look normal. O2 downstream sensor not reporting anything close to a steady reading but varying between both extremes, monitoring live data. Before jump to CAT replacement, I was looking for any suggested testing while monitoring upstream and downstream sensors, to isolate other issues that could be at fault or at least contributors.
Performance and MPG is completely normal across all loading ranges. Coolant temp sensor is reporting 60⁰ at cold startup with ambient temp around 40⁰. Replaced sensor about two weeks ago because of other unrelated issues.
Much thanks in advance for input.
Performance and MPG is completely normal across all loading ranges. Coolant temp sensor is reporting 60⁰ at cold startup with ambient temp around 40⁰. Replaced sensor about two weeks ago because of other unrelated issues.
Much thanks in advance for input.