The RSX IAT sensor is the intake air temperature sensor in your Acura. It plays a big role in the way your Acura Engine Computer Unit controls and delivers the fuel to your K series engine. When the RSX IAT sensor in your Acura goes out, chances are you’ll see your RSX check engine light turn on. This is also known as the MIL status or the Malfunction Indicator Lamp.
When you see your RSX check engine light on, this means that the On Board Diagnostic System has detected a fault. Based on engine inputs, the OBDII system stores a alphanumeric string to help you diagnose the problem. In order to retrieve the OBDII code, you will need a scan tool.
The most common RSX check engine code for a failed Acura IAT sensor is P0113. The specific language behind this trouble code is Intake Air Temperature Circuit High Input.
There may be other stored codes in your Acura, so make sure to check all of them before proceeding.
The RSX IAT sensor is a two pin unit and it’s mounted in your intake pipe.
Replacing your RSX IAT sensor is easy to do and can be done with just a 10mm socket and extension. Today I’ll be showing you how to replace your RSX IAT sensor in a 2003 2.0 liter Acura DOHC i-VTEC.
What does the RSX IAT Sensor Do?
This two pin unit is basically a thermistor device that analyzes the air that’s heading into your 2.0 liter K20 engine. Because cooler air is denser and will require more fuel, your Acura RSX ECU will adjust fuel trims accordingly.
Testing your RSX IAT sensor involves the use of a digital multimeter to measure the internal resistance of the sensor itself.
Replacing your Acura RSX IAT sensor
Before you begin working on your Acura, it’s always a good idea to disconnect the negative terminal of your battery. This prevents any accidental electrical issues and stops you from blowing any fuses.
Open your RSX hood and locate the intake piping from your air box. If you have a RSX cold air intake installed the IAT sensor will be mounted elsewhere. Once you find the two pin intake temperature sender, you can push down on the connector clip.
Depress the intake sender harness and unplug the RSX IAT sensor. Now that you have the sensor unplugged, grab your 10mm socket.
Once the intake sender is unplugged, you can loosen the worm clamp that’s on the throttle body.
Loosen the worm clamps on the throttle as well as the outlet of your RSX airbox.
Now with both of those clamps loosened, you must pull out the metal PCV tubes that are in the intake piping.
Now you can wiggle the intake piping from the throttle body and the air box. Once the accordion intake pipe is taken off, you can flip it over to expose the RSX IAT sensor.
Flip over the intake piping and push closed the clamp to loosen and free the bad intake sender. You can remove the bad unit and install a replacement IAT. Reconnect the intake piping and make sure to tighten the worm clamps to ensure that you haven’t created an intake leak.
Use your OBDII scan tool to erase any stored RSX trouble code. Have any question about this guide to replacing your Acura RSX IAT sensor? Leave us a comment below and let us know!