FK8 Civic Type R Wastegate – Calibration Procedure:

Introduction: Properly calibrating the K20C1 electronic wastegate actuator is the installation hurdle before tuning any Civic Type R with upgraded turbo. Electronic Actuators are common on every modern turbocharged vehicle.

Note: Electronic actuators do not tolerate any misalignment of the turbocharger. It is critical that the turbo is perfectly clocked and the actuator arm oriented to prevent any binding or misalignment. See photo below of proper clocking and installation of turbocharger CHRA center section, as detailed in this document.

Background: To control the boost pressure, the PCM changes the turbocharger wastegate control valve open ratio using the duty control of the stroke of the turbocharger’s electronic wastegate actuator. When the turbocharger wastegate closes, all exhaust gas flows from the exhaust manifold to the turbine and serves as the driving force for turning the turbine. This increases the turbine shaft speed and increases the compression pressure of the fresh intake air, causing the boost pressure to increase. When the turbocharger wastegate control valve opens, some of the exhaust gas bypasses the turbine and flows directly downstream of the turbocharger.This decreases the turbine shaft speed, causing the boost pressure to decrease. This mechanism prevents the boost pressure from increasing excessively, and protects the engine and turbocharger.

The K20C1 turbocharger wastegate is controlled by it’s electric actuator “B” in the above image. This specific wastegate actuator is an electronic stepper motor connected to a linkage “A” which enables flexible and precise control of the turbocharger wastegate control valve open ratio regardless of the operating condition of the engine. This enables the turbocharger wastegate control valve to function as an engine output control device in cooperation with the throttle valve.

The wastegate actual position MUST identically match the computer’s desired aka ‘Commanded’ Position. This is done by clocking the turbo and setting actuator preload with the Full Race linkage “A”.

Instructions to properly install the K20C1 electronic wastegate:

1. Make certain your turbo is clocked and CHRA oriented exactly as shown on page 1

2. Unbolt and Remove the electronic WG actuator from the OEM turbo

3. Attach the large WG mounting bracket “E” to the EFR turbo w/ countersunk M6 screws, then Install Electronic actuator with (4) M6 allen head cap screws

4. Attach Link “D” to the turbine housing’s WG-lever arm

5. Using the stainless steel pivot pin and circlip, fasten “C” to “D”

6. Fasten “C” to the actuator’s threaded rod. This threaded section is where the actuator pre-load adjustments are made, using the Adjustment nut. Be sure to re-use the OEM alignment bushing, but flip it so the shoulder is on the outside of the pivot for maximum range of adjustability.

7. plug in connector

Calibration Procedure: This procedure will be used to physically measure and confirm the wastegate lift voltage at the fully closed and open positions. This may also be useful if you do not have hondata or a laptop able to view the sensors screen. Insert two probe wires into the rear side of pins 3 and 4 of the electronic wastegate connector. Plug the connector into the wastegate.

Wiring / Pins:

#3 BLACK Wire: ground

#4 YELLOW/BLUE Wire: Wastegate Lift voltage

Setting Actuator Linkage with Wastegate Fully Closed

Key on, engine off – measure the voltage between pins 3 and 4 and adjust Actuator Arm threads until voltage is in the range. 1.26V to 1.43V Use a voltmeter to monitor voltage while adjusting the actuator arm Adjusting Nut threads.

When correctly adjusted, the actuator is in the OEM position, ready to control boost. At this point, the turbo kit is installed and the actuator should see 1.26V to 1.43V with key on, engine off to be within range.

DTC P0046: Turbocharger Wastegate Control Actuator Range/Performance Problem

If the actuator arm is not set properly the ECU will throw a code p0046 which means the actuator could hit the mechanical stoppers, and the installer must continue to adjust the actuator so it is operating within the calibrated range. 1.26V to 1.43V with key on, engine off is what the system wants to see. It can allow for up to 6.562% deviation at 0.5seconds before it will throw the p0046 code.

P0046 is an error when the wastegate actuator arm is not fully adjusted and calibrated. The powertrain control module (PCM) monitors the turbocharger wastegate control actuator, and checks the rationality of control deviation and control duty cycle range. In order to provide these tests, actual wastegate position against commanded value and control duty cycle against minimum and maximum rationality thresholds are continuously monitored. If the results of the test are abnormal, the PCM detects a malfunction and stores a DTC.

Calibration Verification– connect Hondata and open the ‘Sensors’ window. Watch WG (wastegate actual position) and WGCMD (wastegate commanded position) – then very carefully adjust the Actuator arm’s threads until the WG and WGCMD are within 0.00-0.02mm from one another. Its not easy to adjust these tiny fractions of a millimeter with a wrench, but go slowly and carefully, you will get dialed in. The screen below highlights the two values in the red box. If these values are out of allowable range, the computer will throw a CEL for P0046 (more later)

If none of this is working for you and you are still getting a code, Hondata suggests to temporarily flash the computer back to stock for troubleshooting to eliminate any programming from effecting your wastegate adjustments, then perform this procedure again.