Not many of the people on here really pay close attention to the vehicle specific forums on here, So not much knowledge on a complicateing question like this gets answered... With older cars a more elite forum is ideal. G3 Integra's billow over HAN and Team integra. Try www.g2ic.com thats where i get all my info from.

Here's what i come across.

code 3 is the MAP sensor. Here's what I found to trouble shoot code 13. (of course I'll adlib in order not to break any copyright laws)

1) Turn ignition off. Remove HAZARD fuse at the battery poitive terminal for 10 sec. This resets the ECU. Turn ignition on. Verify if CHECK ENGINE and LED lights are on. If lights are not on, the problem is intermittent. Test drive, and retest.

2) If the CHECK ENGINE light is on and LED indicates Code 13, turn ignition of. Connect ECU test harness to main harness, not ECU. On A/T models, disconnect 18-pin connector from A/T control unit. Check continuity between C9 and ground.

3) If continuity is there, repair short in RED/WHITE wire between ECU terminal C9 and A/T control unit. If no continuity is present, swap with a known good A/T control unit and recheck. If Code 13 is not indicated, replace A/T control unit.

4) If Code 13 is still present, turn ignition off. Remove HAZARD fuse, like in 1. Swap ECU. Turn ignition on. If CHECK ENGINE LIGHT is on and Code 13 is present, replace ECU (BA sensor is built into ECU).