HR ZDX Throttle Body Install (06-11 Civic Si)

Using a 10mm wrench, disconnect the negative battery terminal.

Start by disconnecting the MAF sensor connector. Push down on the clip and slide off to disconnect.

With a pair of needle nose pliers, squeeze the wire harness clip together while also pulling it away from the housing. Move the wiring out of the way.

With a 10mm socket, loosen the factory hose clamp on the factory air tube.

Pull the air intake tube back and slide it off of the air box lid.

Unhinge the air box lid. There are six hinges total.

Remove the air box lid.

Remove the air filter.

Disconnect the lower section of the air box from the resonator tube.

Remove the lower section of the air box.

Loosen the intake tube clamp from the throttle body.

Remove the intake tube from the throttle body.

Unclamp and remove the valve cover vent tube from the intake tube.

Unclamp and remove the air assist valve tube from the intake tube.

Remove the 10mm bolt mounting the MAP sensor harness mounting bracket.

Unclamp the MAP sensor wire harness from the bracket and discard the bracket.

Unplug the throttle body harness plug.

Unclamp and remove the vacuum hose for the purge control valve solenoid from the throttle body.

Remove the coolant lines from the throttle body.

There is coolant inside of the lines. Be sure to drain the system before disconnecting, or loop the system.

Remove the two 12mm bolts and two 12mm nuts that mount the throttle body to the intake manifold.

Remove the stock throttle body, the gasket will remain attached to the throttle body.

Un-clip the harness from the lower bracket on the throttle body.

Next you will need to remove the studs from the throttle body port on the intake manifold.

Use the two 12mm nuts that held the throttle body in place and place them face to face, as shown in the picture.

Tighten the two nuts together, this will lock the nuts together.

Turn the outer nut to remove the stud. Repeat for both studs.

Prepare the RBC gasket and adapter in the correct orientation to fit on the intake manifold.

Use the shorter supplied bolts to mount the adapter to the intake manifold.

Grab your new ZDX throttle body and prepare it for installation by removing the map sensor from the top port, you will not need this.''''

Use the longer bolts that are supplied with the kit with one lock washer per bolt to mount the ZDX throttle body to the adapter.

Plug in the throttle body harness to the new throttle body.

Prepare the vacuum fitting for installation on the map sensor port on the ZDX throttle body.

Place the vacuum fitting into the port.

Used the supplied bolt to tighten down the bracket for the vacuum fitting.

Install the vacuum hose for the purge control valve solenoid.

Optional: Connect the coolant lines for the throttle body back to the ports on the throttle in the orientation as they were removed from the stock throttle body. These are not necessary for function.

Now you can install your new intake that will allow for the use of a large bore throttle body.

Tuning may be required for the car to function properly with the additional airflow created by the larger throttle body. Your intake manifold must be bored 70mm at the throttle body inlet to achieve maximum efficiency out of the throttle body.