Crankshaft sensor location

Tiny
TOM HAYDON
  • MEMBER
  • 1995 CHEVROLET TAHOE
  • 5.7L
  • V8
  • 4WD
  • AUTOMATIC
  • 180,000 MILES
Trying to locate the crankshaft sensor location on this motor. They sell the sensor at the local auto parts store, but the Chevrolet dealer in parts doesn't think this motor came with one. Then how come they sell a crankshaft sensor for this truck at AutoZone? It's not on the front pulley or no wires coming from behind the starter. Only starter wires are visible. Please help! Thanks, Tom.
Monday, February 25th, 2019 AT 10:16 PM

14 Replies

Tiny
ASEMASTER6371
  • MECHANIC
  • 52,796 POSTS
Good morning,

There is no crank sensor on this engine. You have a distributor that sends the signal to the ECM.

You most likely had an inexperienced parts person at the parts store.

Why did you think you needed a crank sensor?

Roy
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Tuesday, February 26th, 2019 AT 2:31 AM
Tiny
TOM HAYDON
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  • 8 POSTS
So far we have replaced the ignition module, the coil clip came off while driving. The distributor clip some how was partially broken and when and was put on the metal clip inside under the distributor cap backwards meaning the distributor shaft pickup coil clip was put on the ignition module backwards. Now we put on a new pickup coil clip using the old pickup coil wires onto a new ignition module. Put in a new cap and rotor, a new coil. Now we get no spark and no fuel pump motor turn on. We replaced the fuel pump relay switch in the fuse box under the hood. All fuses test good with a ohm meter. YouTube videos suggest we need to change the crankshaft sensor next. They sell them at AutoZone for this truck. They also sell the crankshaft sensor at rock auto website. It has been suggested it could be behind the crankshaft pulley cover and lost. What do you recommend? Thanks, Tom.
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Tuesday, February 26th, 2019 AT 1:37 PM
Tiny
ASEMASTER6371
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Got it.

Again, there is no crank sensor for this motor.

Check the voltage to the positive side of the coil for power. It should have battery voltage.

Wiring diagram attached.

Roy
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Tuesday, February 26th, 2019 AT 1:44 PM
Tiny
TOM HAYDON
  • MEMBER
  • 8 POSTS
Primary coil or pickup coil?
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Tuesday, February 26th, 2019 AT 1:51 PM
Tiny
TOM HAYDON
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  • 8 POSTS
Well, I tested the two pink wires that go in the top of the primary coil and with the key on I get 12 volts.
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Tuesday, February 26th, 2019 AT 2:16 PM
Tiny
ASEMASTER6371
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Primary coil.

Roy
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Tuesday, February 26th, 2019 AT 2:18 PM
Tiny
TOM HAYDON
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  • 8 POSTS
I checked the pink wires and get 12 volts with the key on.
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Tuesday, February 26th, 2019 AT 2:20 PM
Tiny
ASEMASTER6371
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Okay, on the negative side of the coil. Use a test light and crank the engine. See if the test light flashes.

If it does, then the module is working.

If it does not then the module is not working.

Roy
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Tuesday, February 26th, 2019 AT 2:20 PM
Tiny
TOM HAYDON
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Well, the light does not light while cranking motor. This is the third module we have tried. AutoZone parts. First one we got spark but no gas pump motor start. The next two modules we tried we got no spark and no gas. So I guess we go get another module from AutoZone. These modules are all guaranteed for life. Yeah, right.
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Tuesday, February 26th, 2019 AT 2:34 PM
Tiny
ASEMASTER6371
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If there is no light, then the coil is bad. The test light should light up.

Roy
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Tuesday, February 26th, 2019 AT 3:03 PM
Tiny
TOM HAYDON
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  • 8 POSTS
There are two sets of wires from two different locations that plug into the top of the new coil. No other wires are on the top of the coil. The schematic you sent me looks different on top of the coil. Mine has two wire harness that hook together and plug in side by side and the main coil wire to the distributor. I put a pin in both white wires one at a time while cranking the motor. The test light ground was grounded and the tip of the test light was on the needle pin stuck in the white wire while cranking and the test light did not light up. Brand new primary coil.
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Tuesday, February 26th, 2019 AT 3:33 PM
Tiny
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Can you post a picture of where you were testing?

Roy
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Tuesday, February 26th, 2019 AT 3:40 PM
Tiny
TOM HAYDON
  • MEMBER
  • 8 POSTS
I installed a good tested ignition control module and now we get spark. Put a little gas down the carburetor and the motor will start for a few seconds. We turned key on and listened for the fuel pump to come on at the gas cap opening, but no sound coming out of the gas tank. So we have no fuel pump coming on at all. Spark and no fuel. What next can we try? Thanks.
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Tuesday, February 26th, 2019 AT 7:46 PM
Tiny
ASEMASTER6371
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You need to test for power to the fuel pump itself. If you have power then the pump itself is bad.

Roy
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Wednesday, February 27th, 2019 AT 2:23 AM

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