Well, unless if it has been constantly happening over a long period of time, carjacking someone is not a reason enough for a permban. Maybe a warn or a kick would resolve this, but a ban would be too harsh for such a petty rulebreak.
Strange that you ban name does still not appear in the Ban DB. It's been 9 days since the ban, and I am quite sure whichever admin banned you should have added you to the Ban DB if he really did ban you.