[Roadsters] exhaust gas

[Don Boyd]

Couple things: The "0"  O2 means your rich.Not much rich mind you because the
HC isn't sky high.  Could be a lot of things. Get it on a OBDII scanner and
look at the numbers outputting from various sensors. Common problems could be
: thermostat opening too cold, ECT sensor bad, or AMS dirty or going bad.
The high NO is possibly caused by a plugging EGR system. This could also be
the slightly rich cause too.
High HC is too rich or a misfire. Again, the only way is to get the scanner
hooked up and watch the misfire counts.
Changing  plugs is a good idea. Changing oil just before an emission test
reduces HC count somewhat. Check the EGR flow. At 100k it most likely needs
attention. It helps mileage slightly too.
I'm a shop owner that specializes in Euro cars, so this is not Toyota specific
data. Your library has Aldata, you can get access free. It costs me 3k a
year.
Don Boyd