it's obd0. you can have it programmed and chipped, but i was told it's basically a waste of time. what are your plans to use it for? what setup do you have, etc? if it's from a 90 teg, it should be a pr4 as i thought the pr3 was the b17 ecu. i was told that it was also a crx ecu. my 90 teg had a pr4...