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Rb25 Rb20 Cas Differences And Testing

4g6beat

By 4g6beat,
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4g6beat Apprentice

4g6beat

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Posted (edited)

Hi guys,

chasing demons in my cefiro, it's an rb25 with rb20 loom and rb20 powerfc running an rb20 CAS and it's decided to not start,

i've replaced the ignitor loom with a newy but no dice, I'm now testing the cas and AFM as i get 0.4v - 0.8v on my ignitor wires (engine loom side) when cranking and thus no spark, the injectors however are pulsing (and flooding). i've voltage tested the cas by removing and turning it by hand it primes the pump and get's 12v power, 2v to 200 degrees 5v to 1 degree etc when turning but still no ignitor pulse other than 0.4 - 0.8v, so i'm wanting to try a different CAS.

My main question at the moment is can i use my spare rb25 CAS instead of the rb20 CAS to test if the cas is working, as far as i can see from wiring diagrams the 12v,GND 1degree and 200degree signals are on the same pins. i'm aware that using an rb25 cas on an rb20 loom with an rb25 ecu is incorrect as the ecu pinouts are different, but surely with an rb20 ecu fitted swapping CAS's should be fine if the pins are the same. Are there any other diferences i should be aware of between CAS's?

thanks guys

Edited by 4g6beat

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