Bheriya

Hi all! I have a 91 Integra that I just B20B swapped, although this issue happened way before the swap. My ABS Light comes on after 2-3 miles of driving every day and it goes off every time I turn the car off and resets so I cannot check the codes coming off the ABS ecu in the rear quarterpanel. I have tried to read the codes as someone was driving the car and the light on the ecu didn't flash when the ABS light came on the dash. Same with CEL codes, if I unplug a sensor, the CEL will come on when it realizes it, but will then go off and reset when I turn the car off making me unable to read codes. Do you guys know what could be causing this? It doesn't have a CEL right now, just that ever annoying ABS light. This is my girlfriend's daily so I would like her to have ABS.
The ABS light only ever comes on after driving it, if I leave it idling for 30+ mins the light will be off and then i drive it a little and the light comes on. I thought it could be a wheel speed sensor sending the wrong signal making the ECU do the "burnout" code when one wheel is moving at a different rate than the others but I'm not sure on this.
Thanks!

trm4life

The abs computer is in the rear passenger side, next to the rear seat. There should be a small cover you can remove and count the flashes