[QUOTE=mzbmw325i;154011]where did you get the last numbers 153 or 173. under what year E30 did you see it?[QUOTE]
The numbers i mentioned are the last 3 numbers on your ecu. I got it from a search I did and it landed me on a bimmerboard forum page. I sent you a PM with all the ECU numbers that apply for BMW 325i from 87-91. The oil leaks should not affect your rpm's. If you need anymore help you can shoot me a PM and let me know.