Previous UOA here. Now at 100261 miles on the engine.
A little more than halfway through this OCI, my car threw a code for a precat O2 sensor (one of two). The precat O2 sensors on this care are widebands. As I understand, O2 sensors typically fail gradually, so I'm assuming this one -- and thus the engine -- had been running sub-optimally for some time before now. I'm also assuming the other one wasn't far behind. Maybe that partly explains my historically high fuel dilution numbers. Hoping so. Replaced both about 2k miles before the drain and the car ran noticeably better.
Also ran a bottle of Techron in the fuel tank about 1000 miles before the drain.
Copying the numbers here because Polaris's reports are kind of annoying to read:
Iron - 8
Chromium - 0
Nickel - 0
Aluminum - 2
Copper - 2
Lead - 0
Tin - 0
Cadmium - 0
Silver - 0
Vanadium - 0
Silicon - 13
Sodium - 3
Potassium - 2
Titanium - 0
Molybdenum - 49
Antimony - 1
Manganese - 0
Lithium - 0
Boron - 47
Magnesium - 30
Calcium - 2365
Barium - 0
Phosphorus - 735
Zinc - 920
Fuel Dilution - 1.8% (GC)
Soot - Water -
Viscosity @ 100º C - 17.7 cSt
TBN - 4.19
Oxidation - 12
Nitration - 10
Particle Quantifier (PQ) Index - 12
A little more than halfway through this OCI, my car threw a code for a precat O2 sensor (one of two). The precat O2 sensors on this care are widebands. As I understand, O2 sensors typically fail gradually, so I'm assuming this one -- and thus the engine -- had been running sub-optimally for some time before now. I'm also assuming the other one wasn't far behind. Maybe that partly explains my historically high fuel dilution numbers. Hoping so. Replaced both about 2k miles before the drain and the car ran noticeably better.
Also ran a bottle of Techron in the fuel tank about 1000 miles before the drain.
Copying the numbers here because Polaris's reports are kind of annoying to read:
Iron - 8
Chromium - 0
Nickel - 0
Aluminum - 2
Copper - 2
Lead - 0
Tin - 0
Cadmium - 0
Silver - 0
Vanadium - 0
Silicon - 13
Sodium - 3
Potassium - 2
Titanium - 0
Molybdenum - 49
Antimony - 1
Manganese - 0
Lithium - 0
Boron - 47
Magnesium - 30
Calcium - 2365
Barium - 0
Phosphorus - 735
Zinc - 920
Fuel Dilution - 1.8% (GC)
Soot - Water -
Viscosity @ 100º C - 17.7 cSt
TBN - 4.19
Oxidation - 12
Nitration - 10
Particle Quantifier (PQ) Index - 12