i say re-check the wiring
i found this on the internet as well its for an R34 with an RB25neo
hope it helps
A (not so) quick run-down of ECU Power Supply and main Sensors’ Wiring for the R34 GTT’s RB25DET ‘Neo’ engine…
I havent included colour coding for wiring as I dont have access at this time to that info, but I will edit this thread as I get it.
This is a basic “guide” and also not yet complete… and although I trust the info here is 100% accurate, I would welcome anyone who knows different to let me know (which im sure they would ) and I will ammend this thread accordingly.
ECU permanent -12v Earth (vehicle ground) connections:
Pins 25, 32, 116, 124.
ECU permanent +12v (constant battery +12v) connections:
Pins 80 and 109.
ECU switched +12v (when ignition is in the ‘on’ position) connections:
Pin 31 (switched +12v output from the Ignition Relay).
Pin 24 - This feed is from the ignition barrel, (when key is in the ‘IGN’ or ‘ON’ position), and it also supplies the +12v feed to the Injectors, and tells the ECU to ‘switch the power on’, for the Crank Angle/(position) Sensor, and the Air Flow Meter.
Pins 67 and 72 :- Supplied their +12v by the Ignition Coil Relay, which is ‘switched on’ by the ECU when it detects the ignition switch is in ‘on’ position.
Ignition “Start” signal to ECU:
The Ignition Barrel’s “start” signal output (marked as R on barrel, and not to be mistaken for the feed from the ‘start’ output, as this is what switches the starter motor on) is fed to ECU Pin 20, and when the ECU detects this supply, it begins monitoring the CAS for the relevant data to start the engine… ie 1 & 120 degree signal.
Ok, thats the ECU main power supply dealt with.
Now for the Sensors/Control systems’:
Crank Angle Sensor & Air Flow Meter.
The power supply (+12v) for these sensors is also from the Ignition Coil Relay switched output.
The -12v supplies are from different sources for each tho…
The CAS is wired to vehicle/engine ground for its -12v power.
The AFM uses a -12v output from the ECU - Pin 55.
The AFM’s signal output to the ECU, goes to ECU Pin 54.
That’s the Air Flow Meter all done.
The CAS has 2 outputs (1 degree & 120 degree signals) and are connected as follows:
1 Degree Signal - ECU Pin 46.
120 Degree Signal - ECU Pins 44 and 45.
The Throttle Control System components:
Throttle Position sensor :-
+12v supply from ECU pin 48 runs to the TPS, the Turbo boost pressure sensor, and the A/con refrigerant pressure sensor.
-12v for these sensors is supplied by Pin 43 of ECU, (which is also the -12v feed for the Engine Temperature sensor).
The TPS variable output to the ECU is to Pin 23.
The throttle’s output is then automatically adjusted (if need be) by the…
Throttle Control Unit.:-
Sometimes also reffered to as the Traction Control Unit…
I wont get into this just now, as it is AFAIK a secondary system, which modulates the output from the TPS.
Also, people may want to avoid using it for obvious reasons.
And AFAIK, (as with Cepe’s conversion into R32 body) certain functions of this unit will not be able to function correctly without the correct ABS/Traction control systems from the R34 models.
If anyone can say for sure otherwise, then please add your input also.
Engine Temperature Sensor:
(Not to be confused with the temperature gauge sender).
ECU Pin 43 supplies the -12v to the sensor.
The variable signal voltage from the Temp Sensor, is monitored by ECU Pin 56.
Sorry, I havent put that part (Pin 20’s function) in yet.
It is connected to the “start” signal (from ignition barrel connection “R”).
You should see that the +12v feed from the Ignition Relay is supplying the malfunction lights +ve power and the supply to switch it on is from Pin 17… so I will edit that part properly.
I did overlook the Pin 17 as being an input, well spotted.
And thanks for correcting me.