After I get the V3 harness (that looks very professionally built - in my opinion):
A - identify every sensor wire and label it accordingly.
On V3 harness, just 4 of injectors (1-4) and WBO2 sensor are properly hooked up, the remaining sensors and the coils must be wired and couplers to be installed.
so, I will describe what sensors I was identified, in order, starting with the one next to EC couplers:
1. TPS , 3 wires, black - ground, yellow - +5v (for TPS only), green - TPS signal; TPS coupler must be installed (the TPS sensor can be find on M50 engine on the right/ lower side of the throttle body); the OEM coupler to be used is also 3 wires (brown-ground, brown&black-signal, red&white- +5V); the brawn&black wire is in the middle and is the signal wire, depending how you will connect the ground and +5v input, you will get a rising or a falling signal when throttle kicked (so, the green wire should be wired in the middle)
2. IAT, 2 wires, black - ground, blue - IAT signal; IAT sensor on M50 is on the right side of the plastic intake manifold, just next to the throttle body; OEM coupler is 2 wires (brown - ground, brown&white - signal)
3. MAP, 3 wires, black - ground, green - MAP signal, white - +5v common; considering that I do have a unit with built in MAP sensor, I will not use this coupler;
4. FAN, 1 pink wire (+12v); is easy to be identified, being a thicker wire; If you already have a electric fan - you have to wire this pink wire together with a ground (basically on OEM harness, most of grounds are brown)
5. CLT, 2 wires, black - ground, yellow - CLT signal; the CLT sensor is on intake part of the cylinder head and is easy to be identified being the only green or blue; the coupler is also 2 wires, and is also green or blue colored (the OEM wires are: brown - ground, brown&red-CLT signal); attention: the close by black coupler with just 1 brown&white wire is the warning signal for engine overheated and is directly connected to the dash board - after you will remove the OEM harness, you have to re-wire this temp probe directly to th dash board;
6. Crank sensor (VR1), 3 wires, black - ground, brown - VR1 signal, white - +5v common (not used for VR sensors, just for HALL); the OEM sensor can be find under the water pump (or viscous fan) in the left side of the trigger wheel; the stock harness have 2 couplers for this sensor: one close to the sensor, and the second one - just under the intake manifold, very close by the ICV (actually there are 2 couplers in a plastic holder, one in top of another - one is the crank sensor, and the other is the camshaft sensor); I will recommend that the V3 harness to be linked with this 2 sensors on the 'middle' couplers, the wires from these couplers to the sensors being very strong and high temp resistant. attention: there is a 3-rd coupler with 3 wires and the same shape as crank and cam sensor couplers - this is the ICV coupler; unfortunately I never knew which is which and alway i was installed these couplers by 'try and miss' ...
7. Camsync sensor(VR2), 3 wires, the same as the crank sensor; the difference on the V3 harness is that the crank sensor wire have a red label on it; In this first VEMS installation my aim is to make it work waste spark and semi-sequential, so the camsync sensor will not be hooked-up in EC coupler (btw: in the V3, the sec trigger is not hooked up in EC, but is labeled, and you can install this later)
8. a yellow coupler with 2 wires - exactely as the injector coupler - that i don't know yet what is doing ... i suppose that is the knock sensor ...
