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YB refuses to even cough.

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Old Feb 23, 2014 | 10:59 PM
  #1  
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From: Hook
Default YB refuses to even cough.

Hello

okay so here's the situation i'm in, I had snapped a CAM after a mounting stud sheered. Had the head rebuilt and sent back. Refit the head and connected everything back together.

The engine cranks but doesn't fire. There is definitely a spark at all 4 new plugs but no signs of the injectors firing.
The fuel pump pressurizes then cuts out as usual and fuel is getting to the pressure regulator.

I assumed from here that the sensors are at fault and proceeded to check them. I found this on here and decided to test what I thought was applicable:
1) Ensure ignition is OFF.
2) Remove rear of ecu plug cover and insert plug back into ecu.
3) Turn ignition back on (do not start engine)
4) MAIN POWER CHECK: Check for DC voltage of at least 11.5V between ecu pins 19 and 20. 12.6v
5) REFERENCE CHECK: Check for DC voltage of around 4.8 to 5.2V between pins 11 and 30. 4.91v
6) MAP SENSOR CHECK: Check for DC voltage of approx 1.8 to 2.5V between pins 11 and 15. 1.43V.
7) THROTTLE CLOSED:
4x4: Check for DC voltage less than 0.5V between pins 11 and 17. 0.04
2WD: Check for DC voltage greater than 4.5V between pins 11 and 17.
8) THROTTLE FULLY OPEN:

4x4: Check for DC voltage greater than 4.5V between pins 11 and 17. 3.0v
2WD: check for DC voltage less than 0.5V between pins 11 and 17.
9) Turn ignition off, unplug ecu, and turn ignition back on (don’t forget immobilizer if fitted)
10) CRANK SENSOR: Check resistance between pins 3 and 4 between 300 and 1200 ohms. 688
11) CRANK SENSOR: Check AC voltage on pins 3 and 4 while cranking engine - should be at least 2V. 0
11) PHASE SENSOR: Check resistance between pins 5 and 23 between 300 and 1200 ohms. 785
12) PHASE SENSOR: Check AC voltage on pins 5 and 23 while cranking engine - should be at least 1.5 - 2V. 0.05

At this point I stopped to attempt to get a reading for the Crank sensor. After replacing the sensor with a new one and ensuring the gap was correct I still got no reading!
All 4 notches are perfect on the crank but I cannot work out why I cannot get a reading!?
The gap for the phase sensor was also correct but has not been replaced.

The car was run for 2 miles on three cylinders due to the broken cam, could the phase sensor be at fault aswell now because of this?

The MAP sensor and throttle position sensor both under read significantly as well, is there a loom fault here causing all these errors?

I am also presuming that without any of these sensors the ECU wont fire the injectors?
I've basically come to the end of my knowledge and would very much appreciate a push in the right direction.
Thanks for your help in advance.
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Old Feb 24, 2014 | 07:13 AM
  #2  
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Turbosystems
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which model is it 4x4 ?
sounds like you may have plugged the knock sensor and crank sensor the wrong way round
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Old Feb 24, 2014 | 02:56 PM
  #3  
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From: Hook
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Yes it is indeed a 4x4. What's the best way to be sure about which is which?
I have gone off the fact than pins 3 and 4 are for the crank sensor?

any fool proof way with numbers on the plugs?
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Old Feb 25, 2014 | 06:28 PM
  #4  
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col93saphcos
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From: angus glens,scotland
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Pretty sure it's Crank sensor to white plug and knock sensor to black plug, think that's what mine is,
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Old Feb 26, 2014 | 01:36 AM
  #5  
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From: Hook
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I had the crank to white phase and knock to black. Would having the phase and knock sensors the wrong way effect the reading from the crank?
Is the crank wired up to my digi dash for the RPM reading?
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Old Mar 1, 2014 | 06:20 PM
  #6  
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opposite lock
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From: essex,
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Maybe a pin on the connector /sensor end has been disturbed. Old looms can be fragile.
Is the cps gap correct?
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Old Mar 1, 2014 | 08:34 PM
  #7  
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If the plugs were sparking then crank sensor must of been plugged in right as you won't get a spark without it. Have you checked power at injectors to make sure that they are at fault like you think? Could have plug leads on wrong way round.
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Old Mar 2, 2014 | 08:22 PM
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Are you sure that the HT leads are on correct at the dish cap? I know it may seem a daft question but a lot of folk get cought out with this as you will still get a spark at all cylinders,just at the wrong time!
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