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RB25DET NEO into Cefiro not starting

NeoCef
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NeoCef Rookie

NeoCef

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Posted (edited)

Hey guys, so i am putting a rb25det neo into my cefiro but have run into problems with the wiring and not starting. I have checked all the wiring and powers and earths multiple times but cannot seem to find anything wrong. I seem to have spark from the coils fine but for some reason the injectors do not pulse at all. I have checked with another set of injectors but still no pulse. There doesnt seem to be any error codes either. I have also tested the signals from the CAS and confirmed that it is working correctly and tested continuity to the ecu. Is there something i am missing that could stop it from starting up? I also have a spare ECU from a neo stagea as well that also does the exact same things.

Edited by NeoCef
KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

Are you using the ecu and loom from the Neo motor? Do you have power to the injectors (they earth through the ecu)

Do you have the original CAS  for the Neo motor? Is your Ceffie auto or manual or has it just been converted (in which case you have to short out the switch that stops you from starting it in gear).

NeoCef Rookie

NeoCef

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1 hour ago, KiwiRS4T said:

Are you using the ecu and loom from the Neo motor? Do you have power to the injectors (they earth through the ecu)

Do you have the original CAS  for the Neo motor? Is your Ceffie auto or manual or has it just been converted (in which case you have to short out the switch that stops you from starting it in gear).

Yep using all the neo loom and ecu. Got a 12v ign feed to the injectors and have the original CAS but also have 2 others to test with as well. My cef was auto but been converted and have got the neutral relay bridged. 

robbo_rb180 Grand Master

robbo_rb180

Posted
Posted

So it turns over but does not fire? 

1. Check 12v at injectors and Continuity back to the ecu on the ground side. 

2. Remove CAS and plug in, spin it and listen for injectors pulsing. 

3. If the above is good, Check fuel pump is priming. 

4. If pump is priming, fuel lines are backwards. 

 

NeoCef Rookie

NeoCef

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20 minutes ago, robbo_rb180 said:

So it turns over but does not fire? 

1. Check 12v at injectors and Continuity back to the ecu on the ground side. 

2. Remove CAS and plug in, spin it and listen for injectors pulsing. 

3. If the above is good, Check fuel pump is priming. 

4. If pump is priming, fuel lines are backwards. 

 

Yeah well thats where im really stumped on this, i have checked continuity from injectors to ecu and thats allgood but when i spin the CAS by hand only the coils fire. Ive tested the signals from the CAS for the 1 and 120 degree signals and confirmed that is working correctly and even tested it at the actual pins on the ECU as well. The fuel pump is priming and i have checked that the lines are the right way round.

NeoCef Rookie

NeoCef

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11 minutes ago, robbo_rb180 said:

May be worth getting a hold of a consult cable & download consult software. See if there are any codes of errors. Besides testing another ecu.

Yeah i have actually got one, it shows a code for knock sensor because i havnt got the plugs for them. Would that stop it from starting up?

robbo_rb180 Grand Master

robbo_rb180

Posted
Posted

No, it should still turn over.
I would be talking with who made the loom as if both ecus are not firing injectors thats rare for 2 fried ecus. The loom could also have a an issue damaging the ecu.
Probably time to engage an auto sparky

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