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VT 304 cranks but Not firing

Discussion in 'V8 Development and Modification' started by nes138, Mar 19, 2017 at 3:47 PM.

  1. nes138

    nes138 Member

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    Engine wont start - cranks but no fire, not even a pop

    REPLACED - Ignition module, PCM (No VATS chips), BCM, MAF (glad I have spares but nothing worked).
    CHECKED - ALL the fuses, spark from the leads and coil pack and show spark from both a timing light and a spark gap thingy!, checked fuel pumping with a drain hose after the regulator, override the fuel pump relay to permanently on, tipped fuel down the throat, battery has full power, put an external injector into the harness to check pulse and could feel it twitch, put fresh fuel in,

    Was running and kinda slowed to a stall and that was the last of it.
     
  2. immortality

    immortality Moderator Staff Member

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    Might be time to wire up a temporary engine check light if possible and test for fault codes.

    Alternately get a ALDL cable and hook up a laptop with tunerpro to see what the PCM is doing.
     
  3. nes138

    nes138 Member

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    Here lies the problem, I have lost all coms to the tech2. So as per the thread start I replaced the BCM PCM etc etc
     
  4. immortality

    immortality Moderator Staff Member

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    Maybe you have fried something in the wiring?

    Do you have a multimeter so you can test and make sure the BCM/PCM are getting power etc. Or maybe a problematic memcal?
     
  5. nes138

    nes138 Member

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    multiple memcals in the PCMs.....
     
  6. immortality

    immortality Moderator Staff Member

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    Have you checked the ignition timing?

    If you have fuel and spark you should have broom broom.
     
  7. gtrboyy

    gtrboyy Active Member

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    Never used tech2

    But just put into diagnostics mode read flashing faults off test light see if anything comes up that way.
     
  8. nes138

    nes138 Member

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    Very easy, I have not hooked up the engine check light yet, I pulled all the wires out of the cluster to attach to my "analogue" instruments, hence the tech2
     
  9. nes138

    nes138 Member

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    Still nothing although the Tech2 is showing a connection and can read data - NO FAULTS
     
  10. Not_An_Abba_Fan

    Not_An_Abba_Fan Exhaust Guru

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    If it slowed to a stall then I'd be looking at fuel. Check the fuel pressure in line, not just the pressure from the line. Hook up your fuel pressure gauge between the rail and the regulator.

    Have you pulled the spark plugs to see what they look like?
     
  11. nes138

    nes138 Member

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    Will pull the plugs and have a look and check the pressure before the regulator but the flow was about 2.5L/minute and so with that flow rate assumed that it [pressure] was good enough
     
  12. Not_An_Abba_Fan

    Not_An_Abba_Fan Exhaust Guru

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    Volume means little on EFI, it needs both, but pressure is more important.

    The plugs will tell you if it's been firing at least.
     

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