P1406 Chevrolet - EGR Valve Pintle Position Circuit
- Faulty Exhaust Gas Recirculation (EGR) valve
- Carbon blockage of the pintle
What does this mean?
The P1406 code means that the EGR valve is 10% of the expected position by the Powertrain Control Module (PCM), usually caused by carbon built up n the EGR valve. Start by cleaning the EGR valve.
What does this mean?
When is the code detected?
The EGR pintle position was ±10% of the expected position.
- Engine Light ON (or Service Engine Soon Warning Light)
P1406 Chevrolet Description
The Powertrain Control Module (PCM) determines that the EGR valve is stuck open if the actual Exhaust Gas Recirculation (EGR) position and the learned closed EGR position vary by more than a predetermined value. The PCM tests for a stuck valve when the desired EGR position is at 0%. The PCM commands the EGR valve to 100% during certain driving conditions in order to clear a possible restriction from the EGR valve if the PCM determines that the valve is stuck open.how to clean the EGR valve for a p1406 code:
Things You'll Need
Park the car and allow the vehicle ample time to cool off, about a half hour.
Open the hood of the vehicle and locate the EGR valve. You can find the EGR on GM models on the intake manifold. Location may vary slightly from model to model, so it's best to refer to your repair manual. The valve looks like a mushroom top component with a hose and electrical connector coming off it.
Pull the vacuum hose gently from the valve to remove it. Squeeze the sides of the electrical connector and pull the connector straight off. Place both components to the side to ensure they do not get damaged during the removal process.
Use a socket wrench to loosen and remove the two bolts securing the valve to the mount. Turn the wrench counterclockwise until you remove both bolts. You can now remove the loose valve. Lift the valve straight off the mount using some force.
Place the EGR valve in a small bowl with about an inch of carburetor cleaner. Make sure only the bottom part of the valve is soaked. Leave the valve overnight to allow the cleaner to penetrate the carbon.
Use a wire brush, small pick and a rag to clean the valve. Be careful not to damage it. Push open the valve and clean any carbon debris or build up. The valve should now move freely. Allow the valve to air dry completely.
Reinstall the valve. Align the valve on the mount so the holes on the valve match the holes on the mount. Insert the two bolts and tighten using the socket wrench. Plug the vacuum hose back into the valve. Reconnect the electrical connector, then push it into place until you hear it click secured.
An idle relearn procedure is a way to reprogram the vehicle's computer memory to idle at a specified RPM, or revolutions per minute. Without the programmed idle, the vehicle can run arbitrarily, resulting in unnecessary engine wear.
Chevy uses a simple idle relearn process. After you replace the computer chip, it will automatically reset itself when you turn the ignition key from the "on" position to the "off" position. Blue Streak Electronics recommends to warm the engine after the idle relearn procedure, without use of the air conditioner. After the engine is warm, switch the air conditioning on and off, and then put the transmission into the "drive" position. These actions complete the full idle relearn procedure.
It is imperative that a technician verifies that the car's battery is fully charged. If power fails during a relearn procedure, the technician must reprogram the computer chip.