Chart A-5, Cranks But Won't Run (Fuel Pump Problem)

With ignition on, ECM activates fuel pump relay and operates fuel pump. Fuel pump operates when engine is running or cranking, and ECM is receiving ignition reference pulses. If no ignition reference pulses are received, ECM will turn off fuel pump within 2-3 seconds after ignition is switched on. ECM is located under left side of instrument panel, near kick panel. Fuel pump relay resistance should be 56-84 ohms.

1. This verifies fuel pump operation.
2. This checks fuel pump wiring circuit. Fuel pump relay is mounted on ECM located under left side of instrument panel, near kick panel.
3. This ensures ECM is sending a signal to fuel pump relay for 2-3 seconds.
4. Checks fuel pump relay signal from ECM.

Fig 1: Chart A-5, Flow Chart, Cranks But Won't Run

Courtesy of GENERAL MOTORS CORP.

Fig 2: Chart A-5, Schematic, Cranks But Won't Run

Courtesy of GENERAL MOTORS CORP.