Piggyback Heaven : 2JZGTE Super AFC Install

Piggyback Heaven : 2JZGTE Super AFC Install


Today we’ll be looking at the install of a piggyback of a Apexi Super AFC into a MKIV Toyota Supra, equipped with the twin turbo 2JZGTE engine. If you haven’t already check out our tuning primer which gives you a good overview on how to tune your AFC or similar piggyback device.

Before you begin, it’s important to realize just how this little box is controlling your car’s fuel trims by indirectly altering the MAF or MAP input to the PCM. By altering this value, the AFC can artificially trick your ECU into thinking that you need more or less fuel depending on engine load, rpm and throttle position. This part is critical to understanding your 2JZGTE Super AFC Install.

What you will need to complete this job:

  • Wire Strippers or scissors
  • Pliers
  • 10 mm socket and handle

The AFC NEO unit is accompanied with all the hardware necessary for the install.

  • 2 quick splice wire connects
  • 1 male bullet style connector
  • 1 female bullet style connector
  • 1 square piece of double sided tape
  • 2 tie straps

Let’s begin by reviewing the style of wiring we will need for this vehicle, as it’s a USDM 2JZGTE equipped with a MAF sensor, you will be wiring for Karman reading on your AFC.



First and foremost, disconnect your negative terminal on your battery. If you have a stock stereo, now might be a good time to hunt down your radio code before disconnecting the battery.

Next, locate the ECU of this USDM MKIV Toyota Supra which is under the passenger side floor panel. Pull up the carpet to reveal the kickpanel and brackets that secure the ECU and protect it from damage.



Remove the passenger side kickpanel, pull up the carpet to reveal the mounting plate, undo the 10mm nuts holding the mounting plate over the ECU. This plate must be put back upon completion of this install as it protects the ECU from any damage.



With the panel removed, you can now see the manual transmission ECU, undo the 10mm bolt that holds the ECU clips in place, and pull away gently.



Now take this time to review the 2JZGTE Super AFC Install ECU pinouts shown above, we will be connecting the power and the ground wires first.

Single out the one power wire and 2 ground wires ( for older AFCs ) if you are installing a AFC NEO, the power wire will also have a red wire with white stripe. If you are wiring a newer style AFC NEO into this PCM, reference your NEO chart to see the sequence in which the red power wire and the red wire with white stripe must be installed.




Make sure you disconnect the ECU before you begin the 2JZGTE Super AFC Install.

We will be taking the RED AFC wire (12v+) and splicing that into the 2JZ ECU pin 31, if you own a AFC NEO you will be duplicating the ground wire install in that you will be spacing out the red wire and red with white stripe wire.

Now splice the Brown wire (ground 1) into ECU pin 69 which is ground, close to the ecu. Splice the Black wire (ground 2) into the same pin 69 at least 3 cm away from the Brown wire. Take a look at the wiring below as an example of how to wire these 2 ground wires in place. DO NOT MIX THIS UP.



Now move onto the RPM signal, which is your Green wire. This wire is spliced into your 2JZ ECU Pin 58 as it’s the ignition signal from your ignitor, this signal will allow your AFC to know exactly what RPM your engine is operating at.

Now locate your AFM (KARMAN – MAF) AFC Wires which in this example is white and yellow. These wires will connect to the only wire that you need to actually cut, as you will be interrupting the signal from the ECU to the motor and vice versa.

Locate wire 66, which you must cut in order to complete your wiring job. Make sure to leave yourself enough slack and wire to work with as you will be connecting the AFC wires to either side shortly.



As per the AFC diagram shown, connect the Yellow wire to the ECU Side of wire 66 and then connect the White wire to the 66 wire heading AWAY from the ECU harness.



Now find wire 43, which is your Throttle position wire.



You will be splicing the gray wire for throttle position input into that wire 43.



Wrap all your connections up in electrical tape and zip tie any and all wires securely out of the way as to not interfere with your cars operation.



You are now done! Plug your ECU back in and make sure to secure with the 10mm bolt.

Setting up your SAFC

You will want to go to MENU > ETC

and select 6 Cylinder motor, with the arrow pointing up



Make sure that you have the KARMAN setting, as your USDM 2JZGTE is a MAF driven motor. If you are operating on a JDM version of the 2JZGTE, you will want manifold absolute pressure (MAP) setting.

Are you installing a HKS VPC at the same time? Or need a How to Tune your HKS VPC guide?

You are have now completed our 2JZGTE Super AFC Install, and are ready to tune your MKIV!! Enjoy!


    • Hi key, the AFC neo can assist you in reducing fuel cut but if you are pushing the stock fuel pump too far, no amount of adjustment from the AFC will help.

      Remember that fuel cut will happen when your injector pulsewidth is too high for too long. If you are having this problem, try to lower your boost levels and lean you fuel trims until you can get a fuel cut defenser or boost cut controller.

      Refer to our handy How To Tune Your SAFC as well as our How to Install a HKS FCD for more information. Thanks for commenting