TEST 2: EGR Pintle Position Sensor Performance Test
The pintle position sensor produces a voltage signal that increases when the pintle opens and decreases as the pintle closes.
If the pintle position sensor is bad, it'll generally stay stuck, producing a single voltage value as the pintle opens/closes.
You can easily verify that the pintle position signal increases/decreases with a multimeter and by physically pushing the pintle in and releasing it.
CAUTION: The EGR valve has to be removed from the engine to perform this test. If the engine has been running for any length of time, let it cool down. The EGR valve can get very hot! Take all safety precautions to avoid burning your fingers or hands.
Let's get going:
- 1
Remove the EGR valve from its place on the engine.
IMPORTANT: Reconnect the EGR valve to its electrical connector if you had to disconnect it before continuing to the next step. - 2
Place your multimeter in DC Volts mode.
- 3
Connect the red multimeter test lead to the wire that connects to the female terminal labeled with the letter C.
- 4
Connect the black lead of the multimeter to the battery negative (-) terminal.
- 5
Turn the key to the RUN position but don't crank or start the engine.
- 6
Your multimeter should register 0.6 to 0.9 Volts DC at this point.
- 7
With a small screw-driver push the EGR pintle up and into the EGR valve.
- 8
The multimeter should display an increasing voltage reading as you push the EGR pintle up into the EGR valve.
The maximum attainable voltage, with the EGR valve's pintle fully pressed into the EGR valve, will be about 4.5 Volts DC. - 9
Release the EGR valve's pintle back to its fully seated position.
- 10
The voltage reading should return to the value you recorded in step 6.
- 11
Repeat steps 7 thru 9 several times to make sure of your test result.
Let's take a look at what your test results mean:
CASE 1: The voltage increased/decreased as you pushed/released the EGR pintle. This is the correct test result and tells you the EGR valve's pintle position sensor is working correctly.
You can also conclude that the EGR valve pintle position sensor is getting 5 Volts and Ground from the PCM.
If your vehicle is a Chevy Beretta or a Chevy Corsica, your next step is to ensure that the EGR valve solenoid is getting Power. Go to: TEST 5: Making Sure The EGR Solenoid Is Getting 12 Volts.
If your vehicle is a Chevy Cavalier or a Pontiac Sunfire, your next step is to ensure that the EGR valve solenoid is getting Ground. Go to: TEST 6: Making Sure The EGR Solenoid Is Getting Ground.
CASE 2: The voltage DID NOT increase/decrease as you pushed/released the EGR pintle. It's not looking good for the EGR valve, but we still need to make sure the EGR valve pintle position sensor is getting 5 Volts and Ground.
For the first of the next two tests, go to: TEST 3: Making Sure The EGR Valve Pintle Position Sensor Is Receiving 5 Volts.
TEST 3: Making Sure The EGR Valve Pintle Position Sensor Is Receiving 5 Volts
Like most of input sensors the fuel injection computer uses to manage the engine, the EGR pintle position sensor receives 5 Volts DC.
Without these 5 Volts, it won't function and produce a pintle position sensor signal.
Your next step, and the focus of this section, is to check that the gray wire connecting to the terminal labeled with the letter D is delivering 5 Volts to the EGR valve.
These are the test steps:
- 1
Place your multimeter in Volts DC mode.
- 2
Disconnect the EGR valve from its pigtail connector.
- 3
Connect the black multimeter test lead to the battery negative (-) terminal.
- 4
Gently probe female terminal labeled with the letter D with the red multimeter test lead.
- 5
Turn the key to the RUN position but don't crank or start the engine.
- 6
The multimeter should read 4.5 to 5 Volts.
Let's interpret your test results:
CASE 1: The multimeter registered 5 Volts. This is the correct and expected test result.
Now that you've confirmed that the EGR valve is receiving 5 Volts, your next step is to see if its getting Ground. For this test, go to: TEST 4: Making Sure The EGR Valve Pintle Position Sensor Is Receiving Ground.
CASE 2: The multimeter DID NOT register 5 Volts. Without these 5 Volts, the EGR valve's pintle position sensor will not function.
Although it's beyond the scope of this tutorial, your next step is to find out why these 5 Volts are missing and restore them.
TEST 4: Making Sure The EGR Valve Pintle Position Sensor Is Receiving Ground
Up to this point, you've confirmed that:
- The EGR valve pintle position signal is stuck in one value (TEST 2).
- The EGR valve receives 5 Volts from the gray wire connecting to terminal D (TEST 3).
The next order of business is to ensure that the EGR valve pintle position sensor is receiving Ground.
The wire that delivers this Ground is the black (BLK) wire of the EGR valve's connector.
The BLK wire connects to the terminal labeled with the letter B in the illustration above.
Ground should be present in female terminal B with the key in the ON position.
CAUTION: Ground is provided internally by the PCM. So be careful and don't short this terminal (circuit) to battery 12 Volts, or you'll fry the PCM. The multimeter voltage test suggested in the instructions below is a safe way to check for the presence of Ground in this circuit.
These are the test steps:
- 1
Place your multimeter in Volts DC mode.
- 2
Disconnect the EGR valve from its pigtail connector.
- 3
Connect the red multimeter test lead to the battery positive (+) terminal.
- 4
Gently probe female terminal labeled with the letter B with black multimeter test lead.
- 5
Turn the key to the RUN position but don't crank or start the engine.
- 6
The multimeter should read 10 to 12 Volts DC.
Let's interpret your test results:
CASE 1: The multimeter registered 10 to 12 Volts. This is the correct and expected test result and confirms the EGR valve pintle position sensor is receiving Ground.
You can conclude that the EGR valve is bad and needs replacement if you have:
- Confirmed the EGR valve pintle position signal is stuck in one value as you opened/closed the pintle (TEST 2).
- Confirmed the EGR valve pintle position sensor is receiving 5 Volts (TEST 3).
- Confirmed the EGR valve pintle position sensor is receiving Ground (this test section).
CASE 2: The multimeter DID NOT register 10 to 12 Volts. This test result confirms the EGR valve pintle position sensor is not receiving Ground. Without it, the EGR valve's pintle position sensor will not be able to create its position signal.
Although it's beyond the scope of this tutorial, your next step is to find out why Ground missing and restore it.
