As for the car number, there actually do not have any exact feng shui analysis for them. Under feng shui,
1. Most will go by sounding of the number for eg 1848, 3388 or 9988. The other numbers all would be ok
except for maybe the 4 which sounds like death in cantonese.
9354 sound like or jiu-san-wu-si which sound it inauspicious and a bit aggressive.
Remember the power of our mind is very powerful and you keep thinking it is bad it will become very bad.
2. Others is to determine the plate no is an auspicious gua number or not.
for example 9354 = 9 + 3 + 5 + 4 = 21 = 2 + 1 = 3.
If your gua is 3, then this is considered a favourable number for you.
Of course there are other methods. This really depends on how you assess the number.
Black colour is normally defined as Water element. As a weak water person, then black is a favourable colour for you.
cheers.