no spark

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Relenting

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96 GMC k1500 4X4 5.0 son was driving went to turn and it died in middle of turn. Had no fuel pressure so changed fuel pump. Now no spark from coil have changed crank sensor cam sensor coil and icm all have power going to them. I was told to check the pulse wire coming from crank sensor with a test light to see if it pulses when cranking it does nothing. hot and ground wire on crank both tested good. Changed crank sensor pig tail still no pulse from wire wondering if crank sensor is bad out of the box. Another strange thing is the obd2 port quit working at the same time. The scanner will power on but not connect to the brain wondering if it could be a bad brain. ive read some of the other posts and tried what they did but still no good.
 
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Donald Mitchell

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Keep it simple, start by inspeccting the cap and rotor and the distributor parts and the wiring plugs going to it, and the hot wire to the coil, and coil to distributor.
 

Relenting

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Keep it simple, start by inspeccting the cap and rotor and the distributor parts and the wiring plugs going to it, and the hot wire to the coil, and coil to distributor.
New cap and rotor pink wire is hot to coil just nothing coming out of coil. Distributer turns but will make sure it turns smoothly.
 
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Schurkey

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96 GMC k1500 4X4 5.0 son was driving went to turn and it died in middle of turn. Had no fuel pressure so changed fuel pump.
Have you verified that the fuel pump has power? Does it prime when the key is turned from "Off" to "Run"? If it does, the computer has the ability to turn the fuel pump relay on.

Once you get it running, pull the fuel pump relay. Truck should continue to run, with the fuel pump powered by the oil pressure switch and harness. If it doesn't, you'll also need to repair the switch/harness system.

Now no spark from coil have changed crank sensor cam sensor coil and icm all have power going to them. I was told to check the pulse wire coming from crank sensor with a test light to see if it pulses when cranking it does nothing. hot and ground wire on crank both tested good. Changed crank sensor pig tail still no pulse from wire wondering if crank sensor is bad out of the box.
What kind of "Test Light" did you use? If it's the old, incandescent-bulb style, I suspect you'd get no flashing. A "Logic Probe" would be more appropriate because it wouldn't produce an excessive load on the system.

As usual, an actual scan tool would be best.

the obd2 port quit working at the same time. The scanner will power on but not connect to the brain wondering if it could be a bad brain. ive read some of the other posts and tried what they did but still no good.
Verify the fuses that power the ECM. While you're at it, verify ALL the fuses including the big ones. Assure that the wires between the computer and the OBD port aren't damaged. Does the MIL light up when the key is turned from "Off" to "Run"?
 

Relenting

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Not sure a 96 has a ignition control module but a 95 and older when they fail they cause all of you symptoms. That's what I would try.
They have a icm I replaced with one that was suooose to be good. I’m just not getting a pulse from crank sensor. I was told the rpm gauge should bounce when cranking engine but it’s not and I don’t even know if they guy knows what he is talking about.
 

ShadowRejects

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You have quite a series of factors that tie into the crankshaft position sensor, (CKP), Start with simple, check fuses under the hood. Then move to wires. Wouldn't surprise me if you got a bad ground, but also wouldn't surprise me if your ICM is faulty. I've bought a few duds in the 3-4 I've put into mine over the years.
 

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