Nothing, really. Well, the fuel gauge acts a little funny.
This is my second ZX2. The first was a '99 Hot. Liked it so much that when I finally found a '00 SR, I bought it on the spot.
I have a 2000 ZX2 S/R, zinc yellow and I love it! It is very quick, agile, and so easy on gas. My ZX2 gets 320 miles from a tank of gas. The only thing that concerns me about this car is the engine noise. It sometimes seems to "knock". I keep the oil changed every 3000 miles and hope that this "knock" is normal. I hope to keep this car for a long time because I really enjoy it!