Injector pulse problem?

1995 CHEVROLET 1500
140,000 MILES • 5.7L • V8 • 2WD • AUTOMATIC
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BLUECHEVY95
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Hello, I have a 1995 c1500 pick up. I have pulse to one of the injector connectors and nothing to the second one. I swapped the connect on the two injectors, and now the other one is working fine and the other has no pulse. I know both injectors work I just have no pulse to that one connector.
Mar 11, 2023 at 6:36 PM
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JACOBANDNICKOLAS
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Hi,

Each injector will have two wires. Both will have a pink wire. The pink wire is 12v power that is constant and present with the ignition key in the run position or start position. First, confirm both pink wires have 12v.

If they do, injector 1 has a dark blue wire that is the ground. The ground path is provided via the PCM. Injector 2 has a dark green wire that is the ground. Again, the ground path is via the PCM.

So, either we have a faulty connection, a bad wire, or the PCM is failing.

Here is what I need you to do. Once you confirm there is power at the pink wires at both injectors, we need to check for ground. Attach your test lamp alligator clip to the positive battery terminal and probe (one at a time) the dark blue wire and then the dark green wire. With the key on or off, the light should be off.

Have a helper crank the engine. While it is cranking, the test lamp should strobe on and off.

I attached the wiring schematic below, so you have a reference.

Try this and let me know the results.

Take care,

Joe

See pics below.
Mar 11, 2023 at 10:20 PM