I had a little scare last week. I went to get my emissions check before renewing my tags. I failed because, while there were no codes, there were multiple tests that were "Not Ready". I took my ISF to JE Import Performance and they looked and found that my Oxygen Sensor Heater Monitor and my Evaporative System Monitor were both coming back INC(omplete) meaning Not Ready to test. The guy that helped me said the Oxygen Sensor Heater Monitor would always come back as Not Ready because that was necessary with the O2 spoof included with the headers. I followed the instruction in the thread below to make sure my car met all prerequisites to pass the Evaporative System Monitor test. I didn't use my car over the weekend and then drove it around a bunch today. I took it to Advanced Auto and used their OBDII reader to make sure the Evaporative System Monitor test was complete and then went and retested emissions (in Maryland). It passed.

https://www.clublexus.com/forums/is-...pection-3.html

 

another reason why I wont be jamming headers on my car....we really need an ecu tune to get rid of the O2 sensor issues....on my GM LSx cars it was non issue...passed all of my emissions tests with flying colors with long tube headers and no cats.

 

I would say your o2 simulator is not working correctly.... All of my readiness codes set by the time I got home from my header install