The RSX MAP sensor in your Acura is mounted to your throttle body, and it reads information about the air charge heading into your K series engine. By determining the barometric pressure of this incoming air charge, your Acura ECU will know just how much fuel to deliver. The RSX ECU code for the K20A2 is PRB, and the K20A is a PRC ECU code.
When this sensor fails on you the engine computer won’t be able to manage or control the engine properly. There will be several common RSX problems that arise when your RSX MAP Sensor goes bad. Today I’ll be showing you how to test this pressure sensor in a 2005 Acura RSX.
Failed MAP sensor common Acura RSX symptoms
There are many warning signs you will see when the RSX MAP sensor goes out. Most of these Acura RSX problems will be easy to recognize. Here are some of the more common Acura RSX issues that will crop up.
Bad gas mileage
RSX won’t start
Poor idle
Sluggish performance
Check Engine Light ON
When your Acura RSX check engine light is on, you’ll need a OBDII scan tool to retrieve the code. In order to test your Acura RSX MAP sensor, you will need to use a digital multimeter to test the operation of your sensor.
To begin testing your K series MAP sensor, we’ll begin with the power circuit.
Testing your RSX MAP sensor for power
The first wire we’ll be checking for is the power circuit. The part number for this replacement sensor is 37830-PGK-A01, and to test for power you need to turn your RSX ignition to the “ON” position.
Now locate your MAP sensor by following your intake tract from your RSX airbox to your throttle body. Disconnect the 3 prong weather proof connector and you’ll begin by referencing the front of the harness.
The wire you will be checking is on the Acura RSX MAP sensor HARNESS side. The color of this wire is yellow with a red stripe.
Refer to our Acura RSX MAP wiring diagram to find the wire that leads to PIN 1. Place the black lead of your multimeter at the negative battery post, and then gently probe this wire for power.
With your ignition turned to the ON position this wire should return a 5 volt signal. Now you will be checking for a ground signal, which is done at the wire at PIN 2.
This wire is a GREEN wire with a RED stripe in it. To test for ground here at this wire, put the red wire lead at the positive battery terminal and probe PIN 2 with the black lead. Your multimeter should return close to 12 volts of DC power.
If you have power and ground at the Acura RSX MAP sensor, the next part of the test will involve you warming up the sensor to operating temperature. To do this you will need to start your car and allow it to warm up. You can do this by starting your engine and increasing engine RPM to 3000 RPM until your cooling fans kick on.
Now install a jumper wire between PIN 2 and 3, and you will be using a scan tool to read the Live Data in your engine computer. Connect your scan tool and flip to the Live Data section and look up manifold pressure. The value you are looking for is a MAP sensor reading above 101kPa ( 760mmHg, 30in Hg ).
If your scan tool does not read in vacuum and only in voltage, the value you are looking for is greater than 2.8V. If this value does not respond in this manner, chances are that you may have a break in your MAP sensor wiring.
If you suspect that your wiring may have a break in it, or is leading to an intermittent signal from your Acura RSX MAP sensor, you need to check for continuity. The wire you will be checking from is housed in your Acura RSX ECU, located at the 31 pin connector labeled A.Unplug your engine computer harness labeled A with 31 pins in it. Run a jumper from the MAP SIGNAL which is pin 19 to the SG1 pin which is PIN 11. Now check your Live Data scan tool again to check your OBDII values. You should have higher than 2.8 volts at the signal. If they still read lower than 30in Hg then you will need to replace the wire from the signal to PIN 1 of your RSX MAP sensor connector harness.If your Acura RSX MAP sensor does not respond to these testing conditions, you will need to replace it. Remove the 10 mm bolt that secures the unit and gently lift up to remove your pressure sensor. You will need Acura RSX MAP sensor part number 37830-PGK-A01, for a replacement.Have any questions about this testing guide? Leave us a comment below and let us know!
