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Is My Cas Not Working Properly?

jbonez

By jbonez,
in Engines & Forced Induction

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jbonez Enthusiast

jbonez

Posted
Posted

Hey,

Trying to diagnose a problem with my crank angle sensor,

Its an rb25 running an rb20 red top cas. (ems 8860 ecu)

Im not getting spark under cranking conditions, if I turn the ignition on & take the cas out & spin the thing I can see the coils firing and hear the injectors clicking (they coils seem to be firing very fast tho)

Wiring seems in check as far as I can see.

Is this a cas related thing or would neither injectors or spark work if the cas was playing up?

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The Dan Grand Master

The Dan

Posted
Posted

battery faulty or dead. Starter motor drawing too much current. Check earths, check cranking voltages.

If the cas works when you turn it manually, but not when cranking, then it's usually a case of voltage drop when cranking

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slydn32 Rookie

slydn32

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have u looked on ur cam to see if the key is still on it ( little peice of metal that links inside cas ) sorry dont know technical name ! but it wont spin it if its snapped off ..

had similar problem when it didnt link up and cas wouldnt sit properly in.

Really hope this isnt the case otherwise potentially ( could be wrong ) rb20 cas dont work with rb25's ?? good luck

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jbonez Enthusiast

jbonez

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have u looked on ur cam to see if the key is still on it ( little peice of metal that links inside cas ) sorry dont know technical name ! but it wont spin it if its snapped off ..

had similar problem when it didnt link up and cas wouldnt sit properly in.

Really hope this isnt the case otherwise potentially ( could be wrong ) rb20 cas dont work with rb25's ?? good luck

--------------------------

Hey mate, I actually have an ecu that requires the cas wheel to be 1 tooth out, (from 60btdc to 1btdc-10btdc) so instead of spinning the internal trigger wheel I just removed the half moon key. You will find that the key is only for alignment, there is actually 8 grooved teeth that the cas rotates on, the reason people stuff up is they put it back in the wrong way after the tooth has snapped off.

As far as Im aware the cas is internally (trigger discs) the same from r32-r34, however the camshafts & alignment keys change or something similar rb20 & rb25 series 1 cas are the same other then the plug, they both have the half moon alignment key.

---------

The cas must be working fine & it would still spark and carry on if it was out of alignment. I think my earth cable might be too small so im going to try this tonight.

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