60K service completed less than a year ago: new O2 sensors, knock- sensors, filters, fluids, throttle-body cleaning, etc.
HC (PPM) @ 15mph (1578 RPM) MAX/AVERAGE/MEASURED
51/9/49
HC (PPM) @ 25mph (2109 RPM)
35/7/7
Other results were good (CO, NO, O2 (0.0), CO2 (14.8/14.9)). But it almost failed the 15mph HC test. Could this mean the engine wasn't warm enough during the 15mph tests? Or something more serious?