2, 3, 5, and 8 are supplied power by injector fuse 5 in the underhood relay center. Check this fuse and more than likely you will find it open. The ground side of each injector is controlled by the PCM through individual drivers. A faulty ecm would most likely result in one, or another cylinder with no injector fire. If you find the fuse open, either the power side of that respective bank of injectors is shorted, or most likely an injector(s) is faulty pulling too much current. Check the resistance of the injectors(all 8) and you would look for 15 to 17 ohms being good. Any less need replaced. 1991 did have injector problems.
Wednesday, November 16th, 2011 AT 4:28 PM