the code 166 is a normal code that flashes
In the ECM diagnostic section of the manual it explains what happens when you first intialize the diagnostic mode.
The MIL will first display a 166 three times. Code 166 indicates that the ECM based diagnostic routines are functioning.

it should flash this code 3 times
then it should flash any error codes if any are active.

3 basic things to verify
1- is it getting fuel?
2- is it spark?
3-is it getting air?

being a new engine sometimes they just don't fire right up out of the box... try squirting some gas into the intake or use ether and spray a small burst into the air filter housing, just enough to see if it will fire off and run.
If you get no response after that then i would start looking for some other problem that might keep it from running.