73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: Twades87chevy on August 18, 2011, 10:20:16 pm
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ok i have a 1987 chevy 350 tbi 5.7 one ton pickup. the truck run great the night before but this morning the truck will not start. i have a tank full of gas. theres no gas coming out of the tbi at. and it has no spark. i have no clue what went wrong on it. i need your help this is my daily driver. if u need more info just ask. thanks so much for your help.
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No spark, no injector pulse: 1 Verify voltage to the coil. 2. test ignition module and/or replace 3. if you have voltage and the ignition module is good, check for an open or shorted pickup coil.
This is where I would start.
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i have voltage to the coil and i tested the ignition module at the parts place it passed. i might need to replace the pickup coil. but would this keep the tbi injectors from firing gas out. everything on the truck works fuel pump, lights , radio, starter, ac, etc. its just has no spark and the gas is not coming out of the injectors.
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the icm send a signal to the pcm for spark and pulse. even if it test good it can still be bad
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could my computer be bad
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The computer doesn't control the spark until the engine starts, then it is controlling the spark advance not whether or not it has spark.
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ICM and/or Pickup coil are the usual culprits for this problem....
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ok cool im glad i found that out i was about to go buy a new computer. so does the pickup coil have any thing to do with my injectors not shootin gas.
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The icm does
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ok cool im glad i found that out i was about to go buy a new computer. so does the pickup coil have any thing to do with my injectors not shootin gas.
The icm does
Yes. The pickup coil is mounted inside the distributor and gives a signal to the Ignition Control Module (ICM). That signal is processed by the ICM to control the spark and is passed to the computer to control the injector pulse.
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Man thank all so much I'm buying one 2 day. I'll let y'all know if that works
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FYI- The pickup coil can be tested with a simple ohm test.
Post back if you want details.
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that was it i got a new pick up coil and new icm its running great thanks for the help
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just for shots ;) and grins get the coil tested. to see if it was bad