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Old 18-04-2017, 03:12 PM   #1
antman
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Strange CAS Behaviour

Hi guys, I got a CAS related issue when cranking with fully charged battery...no spark at all.
I removed the CAS and turned the CAS shaft by hand and spark and injectors work. Fuel pressure also primes.
Checked loom for breaks/intermittent faults and also checked all earths are ok...fitted new CAS loom connector and tried 2 other known working CAS units..same issue.
I also checked cam turns when cranking...took the plastic cover off the CAS to see it turns while cranking.
Why does CAS not work when on the motor???

What am I doing wrong?
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Old 18-04-2017, 03:33 PM   #2
WazTTed
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have you checked the Cas pin on the end of the cam isnt damaged?
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Old 18-04-2017, 04:30 PM   #3
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Yes I have checked that as well. Also checked that the cas turns when cranking.
Pretty stumped here.
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Old 18-04-2017, 04:55 PM   #4
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Tried a different PTU?

Any error codes?

I'm clutching a straws though.
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Old 18-04-2017, 06:16 PM   #5
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Install the CAS, clear ECU codes then try crank it, then check codes again and see if it throws a CAS code. If no codes and you have the ability to try a hill start without getting your car stuck down the street then that could be a useful test, the ECU may not be getting the 'cranking engine' signal for the starting injection pulses (different to normal running injector pulses).

Also probably check battery voltage, ECU could be starving for power while cranking.
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Old 18-04-2017, 08:12 PM   #6
ProckyZ89
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How are you checking for spark?
So you have spark when the CAS is removed and your turning by hand?..
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Old 18-04-2017, 11:20 PM   #7
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Quote:
Originally Posted by ProckyZ89 View Post
How are you checking for spark?
So you have spark when the CAS is removed and your turning by hand?..
Have another coil pack with plug earthed on top plenum.Yes correct, sparks by turning by hand.
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Old 18-04-2017, 11:23 PM   #8
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Quote:
Originally Posted by Fists View Post
Install the CAS, clear ECU codes then try crank it, then check codes again and see if it throws a CAS code. If no codes and you have the ability to try a hill start without getting your car stuck down the street then that could be a useful test, the ECU may not be getting the 'cranking engine' signal for the starting injection pulses (different to normal running injector pulses).

Also probably check battery voltage, ECU could be starving for power while cranking.
A tow start is a good check....no hills in my ares.. Thanks
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Old 20-04-2017, 04:33 PM   #9
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What voltage have you got across battery terminals when you are cranking engine? What is the CCA or cold cranking amps of your battery?
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