My car keeps just failing government testing. I've checked and adjusted the duty cycle to 47-53 % , but when I check KOEO I see it flash to 70% and then settle to 64%. The readings I've got in the last 2 Aircare tests were as follows
Driving Test
HC Limit 95 ppm (1) 72 (2) 49
CO Limit 0.71% (1) 0.15 (2) 0.12
NOx Limit 1052 ppm (1) 322 (2) 96
Idle Test
HC Limit 108 ppm (1)
161 (2)
137
CO Limit 0.82% (1) 0.02 (2) 0.00
Drivability is good, it starts and idles fine. The last time I had problems like this it was traced to a shorting O2 sensor. The only difference between the 2 tests was an Italian tuneup

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