Smog Test - High HC at 15mph

[t***@yahoo.com]

2000 Lexus ES 300, 65K miles.
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?

[j***@hotmail.com]

Try a bottle of Chevron Techron Fuel System Cleaner next time. Use NGK
Iridium spark plugs. There isn't a lot of tune up you can do in modern
engines.

Post by t***@yahoo.com
2000 Lexus ES 300, 65K miles.
60K service completed less than a year ago: new O2 sensors, knock-
sensors, filters, fluids, throttle-body cleaning, etc.
MAX/AVERAGE/MEASURED
51/9/49
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?