EA11R PNP Installation

We’ve tried our hardest to make installation as straightfoward as possible. First the EFI system is checked. The OEM ECU is removed from the car. Its PCB is removed from the case. The PNP PCB is installed in the Suzuki ECU case. The ECU is then reinstalled in the car. Finally, timing is adjusted with a timing light. If logging and tuning will be required the OEM oxygen sensor is replaced with the wideband lambda controller.

EFI system check using the OEM ECU

Before installing a Kei Sport USA EA11R PNP the rest of the EFI system should be functioning properly and configured correctly. For this, we’ll be following procedures from the EA11R Factory Service Manual (FSM). You should familiarize yourself with these procedures in the FSM. We’ll check the ignition system, the injection system, and the idle air control system.

Basic health

These cars are all old, and many of them have not been well maintained. It’s worth making sure your car is in good health before asking more of it. If you don’t know the service history of the vehicle, assume the worst. Check everything. Replace anything that is suspect.

  • Replace the air filter.
  • Make sure all vacuum hoses and charge hoses are in good shape.
  • Ensure coolant and oil are fresh and the thermostat is new.
  • Do a timing belt and water pump service.

Ignition system check

These procedures are an abridged version of section 6F in the EA11R FSM.

  • Ensure your high-tension cords are in good condition.
  • Ensure that you are using the correct spark plugs for your application:
    • Up to 80 kPa boost (stock): DCPR7EIX
    • more than 80 kPa, up to 110 kPa boost: DCPR8EIX
    • more than 150 kPa (IHI RHB31FW or HT07-4A): DCPR9EIX
  • Ensure the CMP sensor is clean and the gap between the rotor and sensor is 0.2 - 0.4 mm.
  • Ensure that base timing is 5 degrees
    • Jumper pins D and E on the diagnostics connector.
    • Using a timing light, see that timing is 5 degrees. This can be difficult at idle speeds. You can open the throttle to bring engine speed up.

Fuel system check

These procedures are an abridged version of section 6E in the EA11R FSM.

  • Ensure fuel system can maintain 2.2 BAR of fuel pressure. Procedures are described on page 6E-62 of the EA11R FSM.
  • Adjust throttle position switches. Procedures are described on pages 6E-67 of the EA11R FSM.
  • Replace fuel filter.

Idle system check

Adjust idle to ensure it’s within factory specs. Check for vacuum leaks. Replace any cracked vacuum lines and fix any leaking connections.

Remove OEM ECU

The Cappuccino ECU is located behind an interior panel in the passenger side foot well. It’s fastened with two hex head screws. There are two harness plugs which must be removed and then the ECU can be removed from the car.


There are four screws fastening the two case halves together. The OEM PCB has a small metal heat sink that is fastened to a bracket on the case.


Expansion hardware

If you are incorporating any additional features to your PNP system, please see the related expansion section of the PNP documentation before continuing.

Install PNP

Reuse the OEM screws to fasten the new PCB to the case. connect the serial cable to the PCB. Close the case, pinching the serial cable between the two case halves, exiting the case on the same side as the OEM connector. Leave a small amount of the serial cable inside the case loose so that there’s no tension on the cable inside the case. Install the ECU. Route the serial cable to the glovebox.

Install wideband controller and Oxygen sensor

Unplug the OEM oxygen sensor from the wiring harness. Unscrew the oxygen sensor from the exhaust. These are sometimes very, very stuck. Crushing the oxygen sensor with vise grips and breaking it off will allow you to get a stout 6 point socket over the hex of the old sensor and remove it.

If you had trouble removing the oxygen sensor, you should clean and chase the threads. Lisle makes a good thread chaser which is available from most local autoparts stores.

Install the new oxygen sensor in the exhaust. Be sure that there is antisieze on the threads, but not on the sensor.

Connect the oxygen sensor to the wideband controller. Connect the wideband controller to the wiring harness. Tuck the wideband controller out of the way, or zip tie it away from the heat of the exhaust. Behind the battery is a good place for it. We have intentionally provided enough harness for it to reach there.

Post-installation checks

While we have taken efforts to make our system as plug and play as possible, there are variations between cars which can create differences in performance. To maximize performance some post-installation checks and calibrations should be performed, particularly around base timing and wideband calibration.

Check base timing

If you followed the directions above, setting base timing to 5 degrees, then your timing here should be good. DIYAutoTune has a good walkthrough for checking and correcting base timing in TunerStudio. If base timing is not correct, please contact us and we’ll help you correct it.

Check wideband calibration cycle

14point7 has a great write-up and video on correcting the analog signal between the wideband controller and the engine controller. In short, at startup the Spartan Lambda Controller outpus 1.666 V for a short time, followed by 3.333 V for a short time before normal operation. This relates to the following lambda and AFR values:

calibration mode voltage lambda AFR
Power on plus 0-5 seconds 1.666 0.91 13.3
Power on plus 5-10 seconds 3.333 1.13 16.6

To check this, connect your PNP to TunerStudio and watch the Lambda or AFR gauge during startup. This can be double and triple checked by simply turning the car off, waiting 10 seconds, and then turning back on. TunerStudio will connect quickly and you can then watch the gauge. If TunerStudio is reporting values very different than those in the table, contact us and we’ll help you correct it.


If you have any questions or difficulties with installation and startup, please contact us.