RB25 swap problems

[Guest b20turbojason]

I am swaping a RB5det (series 1 motor)into a 75 datsun. i am ready to start it but i am having a problem with the injectors not firing. i have a tester for the injector harness to show them fire and the fire once sometimes twice and then nothing after that. here is my idea of what the problem could be. i had to wire in a igniter into the harness. i dont know why but it wasnt there. i guess it is possible that i got a neo harness. everything else plugs into the motor and into the ecu. also if anyone knows im not sure of the ecu that i am running is the right one. i have gotten 3 rb's and this one that i am using plugs in. but i dont know if the engine company sent tme the right ecu. can anyone tell what the ecu code/number is that i should be using.

 

thanks

jason

[alexideways]

What year is your RB, is it series 1 or 2???

[Guest b20turbojason]

series 1 sorry forgot to put that in

[Careless]

be aware that the neo engines have VVL timing that changes the cam phasing on both intake and exhaust, rather than just intake like on the VCT RB25DET heads if i remember correctly.

 

That might be something to look at, but probably not related to your issue. Perhaps it has to do with different wires being present as well as relocated.

[Z U L8R]

so you have a noid light that blinks when the injector gets it's ground pulse from the ecu, good =]

 

well... now use a test light. one wire is 12volts when the key is in the ignition ON and Start position, verify that u have power. next verify that the ecu is giving ground to the injectors as the engine is cranking. that will let you know that the ecu is good/doing it's job/wired correctly. if you have steady ground pulses from the ecu but not any 12volt power then look on the grey injector harness plug, and give the GREY wire 12volt ignition power. now your injectors should fire.

 

if you're not getting ground pulses from the ecu then either it's not wired in correctly, not getting a reference from the cam angle sensor, or it's bad.

 

good luck

Dave

[alexideways]

Near your ECCM (ECU) plug, you have 1 or 2 relays???

 

Series one have 1 igniter for all coils while series 2 have one igniter per coil, so you MIGHT have the wrong harness, as if you had to wire one in cause it wasn't there, it might be because the igniters are supposed to be straight on the coils themselves...

 

You say that the injectors fires once or twice and then nothing, are all off your injectors acting the same or you tested only one???

 

I don't know what serial # series 1 ecu is, but my series 2 # is 23710 13U00

[Guest b20turbojason]

so i looked at chris rummels wiring and i know why i am having my problem. it is cause i havent given the injectors and vtc power. my problem is my harness is differant then his harness. i dont have 2 white harness clips i only have one. so if anyone can tell me what a air regulator is on the motor i will just trace the wires and figure it out myself. i just dont think that air regulator is what nissan calls it. i could be wrong though.

[chrism]

You shouldn't have to have the MAF connected to get the engine to run. The ECU will detect that the MAF is not sending a signal and cut over to the default value. It will let the engine start but it will not rev.

Upload the FSM that is on this site and look at the diagnostics section for the injectors. That should show you how the injector system is wired and how the ECU controles the injectors. Also check to see if you should have dropping resistors. If the injectors are low impedence, then you should have a set of droppig resistors in the harness. All of this is in the FSM.

[Guest b20turbojason]

i will check it out, but the injectors and everything else is stock except the intake manifold and front mount