Intermittent no-start problems on 1990 P/U

This is most often caused by loose or corroded battery treminal connections. If these are ok, it is usually the ignition wire going from the ignition harness(behind the ignition switch) to the start terminal on the starter(the little wire, not the big one coming from the battery). To check this, disconnect the small wire from the starter, connect a test light or mulit-meter between the small wire and the black(-) terminal of the battery. Have someone turn the ignition switch to the start position and note if the test light lites up. If it does, the wire and ignition switch are ok, if not the wire is bad.