How to add VVT and Wideband Wiring to ATW Engine Harness

[RENOxDECEPTION]

I'll keep this short and sweet, but first, do this at your own risk. I nor Audizine are responsible if you damage your car, start a fire, burn your finger while soldering, or some guy with an S4 steals your girl. Any emissions alterations are illegal, and the car should be used off-road only if such changes are made.


Prerequisites:
VVT tensioner installed from a 06a car as well as a camshaft trigger wheel from a car with VVT.
SAIP deleted following Walky's guide here

Supplies:
018ch or 018m ECU
wideband o2 sensor
1x VW Depinning Tool set: https://www.aliexpress.com/item/3285...27424c4dznOawv
1x Harness tape: https://www.aliexpress.com/item/3279...27424c4dznOawv
1x 1J0973733: https://www.aliexpress.com/item/3305...56ee2515MDz01O
Ecu pins (you can harvest these from a blank spot in your ECU harness)
extra lengths of wire (24 gauge? It's very thin).
A tuner that knows how to code out SAIP.



And finally, to add a wideband o2 sensor to an ATW:

First, disconnect your battery.

Find your primary o2 sensor, unplug the o2 sensor, and remove the sensor closest to the turbo on your Catalytic Converter and replace it with a wideband sensor.

On the o2 sensor connector, slide out the purple retainer for the pins and remove all four pins from the connector using the terminal release/depinning tool linked above.

Your narrowband o2 sensor will have the following pin and corresponding wire colors:
1: green/yellow
2: red/white
3: brown
4: white

Grab your 1J0973733 and additional lengths of wire and add an o2 sensor pin to one end, and an ECU pin to the other end on both new wires.
insert the corresponding wire colors into the connector pins:

1: White
2: (new wire, OEM is colored yellow/red) to ECU pin 71
3: green/yellow
4: red/white
5: Brown
6: (new wire, OEM is colored yellow/green) to ECU pin 52

After you have them inserted, insert the purple plastic retaining clip again.
Plug in your wideband o2 sensor.


Gain access to the ECU box.
remove the large connector from the ECU,
pop off the black plastic cover that prevents access to the wires.
remove purple retainer
after removing the retainer, the pins should come out in two groups, one black group, and one white group.

This diagram should help you locate pin 71 and 52, they are both on the white group of wires.



Walky's guide here has great pictures on how to access the ECU box and add/remove pins from the ECU harness.



As for VVT:

This is how I've added it, there are better ways to do it, but probably none that are as simple. The only issue is that the factory wire gauge is much larger than the wiring I've used, but the solenoid still functions and the wires do not get hot or any other weird effects.

The solenoid has two pins, one for switched power, and the other is ground, which the ECU controls via pin 115. If you decide to run your own wires instead of making use of the already existing N112 SAIP solenoid wiring, that is all you need to know. This guide uses the N112 solenoid wiring and that is the reason for the following note:

NOTE: This REQUIRES that your secondary air injection system is coded out and deleted or you will get a check engine light.

Since the link above for 1J0973733 came with extra pins that you didn't have to use, you're going to use one for this.

Since you're in the ECU harness already, remove pin 9 from the larger of the two ECU connectors (refer to above ECU pinout), you can use a razor blade to depress the retainer on the pin, I've never had an issue with this. Cut the pin off and strip the end of the wire.

Make a new 6" length of wire and strip both ends.

Take the pin from your 1J0973733 kit and use one of the pins.
Crimp it onto the 6" wire and solder if you desire (the gauges are very different for this, so soldering is probably preferred here to ensure a good connection)
Solder the other end of this 6" length of wire to pin 9 you removed and stripped earlier, and be sure to heat shrink them.

The pin goes into the smaller connector of the ECU, pin 115 (refer to above ECU pinout diagram). The purple retainer on these is a little weird, you can use a small flathead screwdriver to push the center of the retainer and then slide it out.

replace the purple retainer and plastic covers.

Use the harness tape linked above to wrap your engine harness however you desire.

Remove the green connector from under your intake manifold for the n112 solenoid, and reroute it over to the back of your cylinder head and plug it into your VVT tensioner.

Slap in your tuned 018ch/m box and that's it; VVT now works and you have a wideband o2 sensor.

You will need to recode your cluster to get rid of a new CEL that emerges when you upgrade.

Your car can still run with the ATW ECU in an emergency, but it is not recommended and it will run like shit.

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If you want to improve this post, feel free to dm me pictures and I will add them to the post with credit.

[EarlySphinx552]

Do you have any specific information on doing the vvt tensioner swap along with the trigger wheel? Does the trigger just bolt to the front of the cam behind the sensor? Is that all that's necessary on the head or does the cam gear need to be changed to match. How does it actually move the cam timing?

[Blazius]

Do you have any specific information on doing the vvt tensioner swap along with the trigger wheel? Does the trigger just bolt to the front of the cam behind the sensor? Is that all that's necessary on the head or does the cam gear need to be changed to match. How does it actually move the cam timing?

Yes trigger wheel bolts up to cam, you just swap up the tensioner and youll have VVT, but you need to be DBW for it.

I run AEB head with VVT :)