Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
When you turn the key to on does the check engine light come on?
It sounds like you have a bad ignition control module. It controls whether the fuel pump will run when the key is on and whenever we see these trucks come in with no check engine light illumination we change the ignition module right away.
I need to step out into the shop for a minute. I'll be back.
I'm sorry, what I thought was a quick job turned into an all morning thing. Have you checked to make sure that you are getting power and ground at the ignition module?
Are you getting power at the fuel pump relay? You should have power on the black/white wire and power from the PCM on the green/white wire at the relay.
So you are getting power to the relay from the PCM but not to the pump?
1. Perform scratch tests using a conventional bulb type test light connected to B+.2. Disconnect the 4-terminal connector at the distributor.3. Turn the key on.4. Touch the test light to the Purple/White wire and check for an injector pulse.5. If no injector pulse, repeat this test at the Powertrain Control Module (PCM) and verify that the PCM is powered and grounded properly, and check for engine RPM on the scan tool when cranking.6. If injector pulse is generated, reconnect the distributor and remove the distributor cap.7. Touch the test light used in step 4 to the Green wire of the pickup coil attached to the ignition control module at the terminal labeled "P" with the key on.8. Check for injector pulse and spark.9. If OK on both spark and injector pulse, connect a Digital Volt Ohm Meter (DVOM) set to AC volts to the Green and White wire of the pickup coil and crank the engine.10. If voltage is less than 0.7 V AC, replace the distributor shaft and pickup coil.11. If no spark is generated during step #7, Verify the ignition coil has good power supply. Connect a test light across the White wire (coil trigger) and the Pink (coil power) and repeat step #7. If the test light blinks, replace the coil.