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Car cranks but wont start

Discussion in '2013-14 Shelby GT500' started by Meerology, Nov 9, 2018.

  1. Meerology

    Meerology Member Established Member

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    Dubai
    After finding out why my engine kept over heating (Head gasket) we reinstalled everything and turned on the car. The car turned on fine but sounded like it was misfiring. We checked everything that could make it misfire but my friend noticed that the serpentine belt was loose, which it was (tensioner wasnt doing its job). We adjusted the serpentine belt and started the car again. However this time it did not start, it would only crank and the engine will turn over but not start. All coils, injectors and spark plugs are working. I even tried a different set of spark plugs. The car basically has fuel and ignition but will not start. All electronics connected to the throttle body are working as well as the maf sensor, crank sensor and cam sensor are fine. We also tried pushing the car, disconnecting the battery, replacing the battery, changing the tune but nothing would start the car. It would only crank and turn over.
     
  2. 50stangpower

    50stangpower Well-Known Member Established Member

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    Westminster MD
    can you do a crank relearn?
     
  3. Meerology

    Meerology Member Established Member

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    I cant because I need to start the car and it doesnt start
     
  4. Snoopy49

    Snoopy49 Well-Known Member Established Member

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    I would check out the connectors on the cam position sensors (4). Is there any indication of RPM on the tach when it is cranking? Have you checked for any codes?
     
    Last edited: Nov 10, 2018
  5. Snoopy49

    Snoopy49 Well-Known Member Established Member

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    Camshaft Position (CMP) Sensor
    The CMP sensor detects the position of the camshaft. The CMP sensor identifies when piston number 1 is on its compression stroke. A signal is then sent to the PCM and used for synchronizing the sequential firing of the fuel injectors. Coil on plug (COP) ignition applications use the CMP sensor signal to select the correct ignition coil to fire.

    Inline engines with 2 camshafts and with variable camshaft timing (VCT) are equipped with 2 CMP sensors. The second sensor identifies the exhaust camshaft position.

    The 2 sensor system on inline engines use the following CMP sensor signal circuit names:

    • CMP11 - bank 1, intake camshaft
    • CMP12 - bank 1, exhaust camshaft
    Engines with 1 camshaft per bank and with VCT are equipped with 2 CMP sensors. The second sensor identifies the camshaft position on bank 2.

    The 2 sensor system on engines with 1 camshaft per bank and with VCT use the following CMP sensor signal circuit names:

    • CMP11 - bank 1
    • CMP21 - bank 2
    Engines with 4 camshafts and with VCT are equipped with 4 CMP sensors. The 4 sensors identify the position of each camshaft.

    The 4 sensor system uses the following CMP sensor signal circuit names:


    • CMP11 - bank 1, intake camshaft
    • CMP12 - bank 1, exhaust camshaft
    • CMP21 - bank 2, intake camshaft
    • CMP22 - bank 2, exhaust camshaft
    There are the 2 types of CMP sensors used. The 2 pin variable reluctance sensor and the 3 pin Hall effect sensor.

    VE2~us~en~file=A23509A_gif~gen~ref.gif

    Typical Variable Reluctance CMP Sensor

    VE2~us~en~file=N0073055_gif~gen~ref.gif

    Typical Hall Effect CMP Sensor
     

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