I am having difficulty getting a good #6 injecter to fire on my 90 NA. CAS fires all spark plugs and injectors #1-5. ECU has been inspected and checks out fine. PTU is sparking all plugs. Pin #114 at ECU harness has continuity to a new injector plug. There exist 12.3 volts at the injector plug w-key off. There exists good ground on all injector plugs. Help??? Is there anyone that has experienced this type of electrical problem? Please advise....