91 Chevy tbi 350 in a 85 CJ7 Crank no start

Discussion in '4x4 trucks / off road' started by Bigbobs, Jan 1, 2013.

  1. Bigbobs

    Bigbobs Member

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    I put a 91 Chevy tbi 350 in my 85 Jeep CJ7. I'm using the painless wiring harness and can get the engine to crank but not start. I'm getting fuel but no spark. I have a new coil and distributor. I was told it could be the Vats system but don't think that that year truck had one. Any ideas?
     
  2. gpmorgan

    gpmorgan Auto Banned

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    are you getting 12 volts to positive side of ign coil?
     
  3. Bigbobs

    Bigbobs Member

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    Yes, I'm getting 12 volts to the positive side.
     
  4. gpmorgan

    gpmorgan Auto Banned

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    how old is the dist? sounds like control module may be bad. could also be rotor. remove coil wire from cap and hold just above coil wire post. have someone try to start it and see if it fires. if the coil fires i would say it is the rotor.
     
  5. Bigbobs

    Bigbobs Member

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    The distributor is new. I replaced it when I did the engine swap because the factory seemed to be in bad shape. I will try when I can get someone up to help me. Thanks.
     
  6. gpmorgan

    gpmorgan Auto Banned

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    if you still have the original dist. at least you've got some extra parts to try without buying more.
     
  7. Bigbobs

    Bigbobs Member

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    No spark from the coil post. Unfortunately I was unwise and got rid of the older parts while back. Lesson learned. So it could be the ESC module? Is there a way to get it checked before I put money into buying a new one. I bought a VATS bypass module that I have not installed yet because I don't think that is the problem. The guys at Painless told me that VaATS system could be causing the no start but I have read that it only turns off the fuel. I have also read that the VATS system did not come on tbi trucks.
     
  8. gpmorgan

    gpmorgan Auto Banned

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    yes the module inside dist. tells the coil when to fire. so really it could be the coil or module. i think most part stores can check coil or module to determine which one is bad.
     
  9. gpmorgan

    gpmorgan Auto Banned

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    Measure the coil primary resistance. Using an ohmmeter, connect the red lead to the coil's positive (+) electrical connector, and the ohmmeter's black lead to the coil's negative (-) electrical connector. An average resistance reading could be between 0.3 and 1.0 ohms.




    7 Measure the coil secondary resistance. Connect the ohmmeter's black lead to the coil's negative (-) electrical connector and the ohmmeter's red lead to the coil's terminal-where the distributor or spark plug wire attaches to. A typical resistance reading could be 8,000 to 11,500 ohms.



    8

    Read more: How to Check an Ignition Coil | eHow.com How to Check an Ignition Coil | eHow.com .......... here is a link on how to check the coil if you have a ohm meter. need to isolate coil by taking the wiring from coil.
     
  10. leolkfrm

    leolkfrm Full Member

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    i think a hei ignition and carb would be the better way to go...bwai
     

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