got a 90 EF with B16A swap and PW0 ecu. started acting up last week by running rough and eventually cutting off. now it will not start at all. got a CEL for code 15, Ignition Output Signal. checked my wiring and all is good. the dist has external coil and is also good. checked ignitor and it tested fine. swapped distributors and still have same problem. also have changed plugs and wires off of working engines. Could it be the ECU? Any advice would be appreciated!