Ideas would be to perform testing using the proper fully functional diagnostic equipment capable for your vehicle and enlisting the use of a shop manual and wiring diagram to follow the proper troubleshooting flowchart for your concern.
How have you verified the "injectors not working"? What diagnostic trouble codes have you retrieved? This is not something the typical "do it yourself" home mechanic can approach.
RepairPal Certified shops can diagnose and repair your 1997 Chevrolet Tahoe. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.