Faulty EGR valve or its internal pintle position sensor, for example carbon-fouled or sticking pintle; Damaged, chafed or corroded wiring to the EGR valve (open circuit, short to ground or short to voltage); Poor connection at the EGR valve or ECM connector, such as bent, loose or corroded terminals; Heavy carbon build-up in the EGR valve or passages preventing normal pintle movement; Fault in the sensor reference voltage or ground supply shared with other sensors; Faulty engine control module.

P1406

EGR Valve Pintle Position Circuit.

Saturn
Powertrain
Manufacturer code
Medium severity

How this code is built

P: SystemPowertrain
1: Defined byThe manufacturer
4: AreaAuxiliary emission controls
06: FaultThe specific fault in that area

What it means

On a Saturn, P1406 means the engine control module has detected a fault in the EGR valve pintle position circuit. The module compares the pintle position signal from the valve's position sensor with the position it has commanded, and sets the code when the signal is out of range, stuck or erratic. The exact valve type and test conditions depend on the model and engine.

Symptoms

Malfunction indicator lamp on
Rough idle or occasional stalling at idle
Hesitation or surging at light throttle
Pinging or knocking (detonation) under load
Slightly poorer fuel economy
Possible failed emissions test

Possible causes

Faulty EGR valve or its internal pintle position sensor, for example carbon-fouled or sticking pintlelikely
Damaged, chafed or corroded wiring to the EGR valve (open circuit, short to ground or short to voltage)likely
Poor connection at the EGR valve or ECM connector, such as bent, loose or corroded terminalspossible
Heavy carbon build-up in the EGR valve or passages preventing normal pintle movementpossible
Fault in the sensor reference voltage or ground supply shared with other sensorsrare
Faulty engine control modulerare

How to diagnose

Read all stored and pending codes and record the freeze frame data to see engine conditions when the code set.
Check for other codes, especially sensor reference voltage faults, which could point to a shared wiring problem.
Visually inspect the EGR valve, its connector and the wiring harness for heat damage, chafing, corrosion or loose terminals.
With the engine off, check the EGR valve for carbon build-up and check the pintle moves freely and returns, following the procedure for that model and engine.
Using a scan tool, compare the commanded EGR position with the actual pintle position reading and see whether it responds smoothly.
Check the 5 volt reference, signal and ground circuits at the valve connector with a multimeter against the manufacturer's wiring data.
Test the wiring for continuity and for shorts to ground or voltage between the valve and the ECM.
If the wiring and supplies are good, test or substitute the EGR valve before suspecting the ECM.

How to fix

Repair or replace damaged wiring and renew faulty connector terminals.
Clean or replace the EGR valve if the pintle is carbon-fouled or sticking and cleaning is permitted for that valve.
Replace the EGR valve assembly if the position sensor is faulty.
Clear blocked EGR passages of carbon as per the manufacturer's procedure.
Repair the sensor reference or ground supply fault if shared circuits are affected.
Replace or reprogram the ECM only after all other causes are ruled out and a fault is confirmed.

Can I keep driving?

Medium severity

The car can usually be driven for a short time, but book a repair soon. Left alone, detonation and poor running can develop, and the emissions control fault may cause further problems.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.