With pre '88 cars you need to consider the possibility of bad engine wireing insulation. Check for 12 volts to ground at the injector plugs with the ignition turned on. One pin of each plug should be zero volts and the other 12. No voltage means a bad injector relay. With the turbo cars it is absolutely critical to ALWAYS use Bougicord plug wires. With cheaper crimped end wires they won't make contact with the pins in the base of the distributor holes. This extra gap will weaken the spark. The engine should run fine but they can cause misfires when the turbo is in use. Also check the tach while cranking the engine. If it doesn't jump a little the Hall effect sensor is bad or the connection/plug is defective.