1989 Chevy Silverado FUEL

Pull a couple of spark plugs. Are they fouling?

Well, that rules out flooding so you need to get a fuel pressure gauge and see if the pressure is within spec

Diagnostic Trouble Codes - 1989
Chevrolet
13 Open Oxygen Sensor Circuit
14 Coolant Temperature Sensor (High Temp Indicated)
15 Coolant Temperature Sensor (Low Temp Indicated)
21 Throttle Position Sensor (Signal Voltage High)
22 Throttle Position Sensor (Signal Voltage Low)
23 Manifold Air Temperature (MAT) Low Temp Indicated
24 Vehicle Speed Sensor (VSS) Circuit
25 Manifold Air Temperature (MAT) High Temp Indicated
32 Exhaust Gas Recirculation (EGR) Circuit
33 Manifold Absolute Pressure Sensor Circuit (High Sig.)
34 Manifold Absolute Pressure Sensor Circuit (Low Sig.)
42 Electronic Spark Timing (EST) Circuit
43 Electronic Spark Control (ESC) Circuit
44 Oxygen Sensor Circuit (Lean Exhaust Indicated)
45 Oxygen Sensor Circuit (Rich Exhaust Indicated)
51 Faulty PROM
52 Fuel CALPAK Error or Missing
54 Fuel Pump Circuit (Low Voltage)
55 55 ECM Error