Car won't crank

Discussion in 'Turbo Trans Am Tech' started by Oscar Pichardo, Jun 24, 2012.

  1. Oscar Pichardo New Member

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    Need some advise on a no crank condition for my TTA with a brand new motor installed.

    Went to start the car and nothing. Turned ignition to on, pump primed for a few seconds and it built fuel
    pressure. Went to crank then nothing. At first, thought it was a VATs issue, but no security light turns on at all, not even with ignition on prior to cranking. I think it was disabled after installing the Classic FAST system. The symptoms point to VATS, but not sure if the lack of a lit security light supports this.

    I ohmed the resistor on the key and the under steering column connector and they match. Tried my spare key. Same no crank.

    I then replaced the starter relay nothing. I then jumper the starter relay harness (Yellow wire to Green/White wire) and got the starter to crank, but no start. This has been the only way I have been able to crank the motor at all is through the jumper on the starter relay.

    Test light on injectors do not light during jumper cranking - checked the plugs after several start attempts
    and they are bone dry. When cranking I have 50+ lbs fuel pressure & fuel pump operation.

    Car has brand new plugs, fuel pump relay, starter relay, injectors. I do keep blowing the IGN 10 amp fuse when I jumper the starter relay and it may be related to issue, but not certain where else to look.

    Cam sensor harness voltage pins B & C at 6 to 9 volts.
    Crank sensor harness voltage pins B & C at 6 to 9 volts.

    This is what I have tried so far, any additional ideas would be much appreciated.

    Thanks,
  2. 86GN-862+2 Member

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    Pinched or old wireharness? Just giving you ideas.
  3. Oscar Pichardo New Member

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    Appreciate the input. Looking at a potential ignition module failure now. The quest continues.
  4. jarredsoon Member

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    wouldn't the plugs be wet with fuel after several attempts to start and cranking over?? Maybe the injectors are not opening? Tough to say. Good Luck on your no start mission.
  5. Oscar Pichardo New Member

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    Got the car to crank by placing a jumper on pins A and E at the starter relay. However, no spark or injector pulse. Does VATs disable both fuel and spark ?
    Check the injector wiring harness for both 12V with ignition on which it has, but no pulsing (injector light does not light) when cranking.

    Also, my Classic Fast box is not registering RPM when cranking.

    Any other ideas ?

    Thanks
  6. Razor Forum tech Advisor

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    The vats relay is loctaed inside your drivers kick panel. You'll have like 4 wires on it. It has two heavier gauge wires on it(starter) and two smaller wires VATS(key)

    Get a test light and confirm power coming into the module and power coming out(when ignition put to crank). All the VATS does is interupt the starter through this relay. If you bypass this module the resistor on key no longer becomes an issue. Has nothing to do with the FAST.

    Hope this helps.
  7. Oscar Pichardo New Member

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    Found the VATs relay by the driver side kick panel.

    Test light ground to the thick yellow wire (power in) during crank showed power (light turned on). However, no power coming out from the thick green w/white stripe
    wire when cranking. Test light did not turn on.

    I ohmed the pellet on both sets of keys and confirmed resistance is same at the two VATs white wires with orange shealthing under the steering column. Not getting a security
    light at all.

    Does this point to the VATs module gone bad ?

    Thanks for the help
  8. Oscar Pichardo New Member

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    Here is picture of the back of what I believe to be the VATs module. Anyone comment on what the pin outs are by wire color ?
    Did not see any callouts referenced anywhere on the unit.

    I believe the 7 wires on the lower left side are going to VAT's module just do not know which pin since colors are different to other VATs pin outs I have seen.
    Plus, where is the 8th wire ?

    The VATs pin outs are below, just do not know what color wire goes for each:
    A1 - Ignition switch input
    A2 - Crank fuel signal
    A3 - Starter enable relay
    A4 - Security Lamp Output
    A6 - Key resistor (Hi)
    B1 - Ground
    B2 - Key resistor (low)
    B8- Battery power.
    Back-VATs.JPG
  9. Razor Forum tech Advisor

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    Jump the two larger wires and get the car started.

    If so.. chicken or egg situation with VATS.
  10. eop002 Member

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    Yes. That's is where I am at. Car cranks when jumpered.
    No spark or fuel when cranking.

    Checking the crank sensor.

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