Seem to have lost fire to # 1 & 2 injectors. Checked all wiring from injectors back to ECU harness wiring checks out, on mult-meter. Also inverted Switch Boxes, problem still there. Jumpered 3 & 4 to 1 & 2 and problem moved to 3 & 4. Does anyone have any suggestions before I take the big plunge and replace the ECU. 