Chrysler P1404 Trouble Code: Diagnosis, Symptoms, and Solutions
The check engine light illuminating on your dashboard is always a cause for concern. When the diagnosis reveals the Chrysler P1404 trouble code, it specifically relates to the Exhaust Gas Recirculation (EGR) system. This code indicates a circuit problem with the EGR Differential Pressure Feedback EGR (DPFE) sensor or its circuit. Unlike other faults, P1404 is often related to an erratic or out-of-specification electrical signal rather than simple clogging. Understanding this code, its causes, and the repair methods is essential for any owner or mechanic looking to restore their Chrysler vehicle to optimal running condition.
What is the P1404 Code and What are its Symptoms?
The P1404 trouble code is a generic code related to the engine control system. On Chrysler, Dodge, and Jeep models, it means “EGR System Leak Detection” or, more technically, a circuit problem with the EGR valve differential pressure sensor. This sensor plays a crucial role in measuring the pressure difference between the two sides of the EGR valve orifice. The Engine Control Module (ECM) uses this data to precisely control the flow of recirculated exhaust gases.
When the signal from this sensor is inconsistent, missing, or out of range, the ECM records the Chrysler P1404 code and illuminates the Malfunction Indicator Lamp (MIL). The symptoms associated with this fault can be more or less pronounced:
- The “Check Engine” light illuminates on the dashboard.
- A slight decrease in engine performance, especially at low RPM.
- An increase in fuel consumption.
- Hesitation or intermittent misfires.
- In some cases, the vehicle may enter a “limp mode” to protect the engine, limiting its power.
Main Causes of the P1404 Fault on Chrysler
Diagnosing the exact source of the problem is a key step before any intervention. The P1404 code on a Chrysler can stem from several sources, often related to electrical issues and connectors.
- A faulty DPFE sensor: This is the most common cause. The sensor itself, sensitive to temperature variations and vibrations, can fail and send erroneous signals to the ECU.
- Damaged or corroded electrical wires: The harness connecting the DPFE sensor to the computer can be damaged, cut, or have corroded connectors, leading to a loss of signal or a short circuit.
- A problem with the connector: A bent pin, corrosion, or a poor connection in the sensor plug can be enough to trigger the code.
- A defective EGR valve: Although less direct, a physically stuck or leaking EGR valve can, in some cases, influence the sensor readings and generate this code.
- A rare ECU problem: An internal failure of the Engine Control Module is a rare possibility, but it should be considered once all other causes have been eliminated.
How to Diagnose and Repair the P1404 Code?
The diagnostic procedure requires a code reader and a multimeter to check voltages and continuity.
- Visual Inspection: Start by locating the DPFE sensor (usually mounted on the intake manifold or near the EGR valve). Carefully inspect the connector, wires, and the sensor itself for any obvious signs of damage, corrosion, or debris.
- Electrical Check: Using a multimeter, check the sensor’s supply voltage and ground (refer to the repair manual for the precise expected values for your Chrysler model). Also test the sensor’s return signal.
- Sensor Test: Some DPFE sensors can be tested by applying vacuum (with a vacuum pump) and observing the change in the voltage signal. A lack of variation confirms sensor failure.
- Connector Cleaning: Clean the connector terminals with an appropriate product to remove any oxidation that could disrupt the signal.
- Replacement: If the sensor is identified as faulty, replacing it is the solution. Ensure you use a quality part specific to your vehicle model. After replacement, clear the code with your diagnostic tool and perform a road test to confirm the repair.
Conclusion: Prevention and Cure
The Chrysler P1404 code, while specific, is generally simple and inexpensive to repair once properly diagnosed. In the vast majority of cases, replacing the DPFE sensor permanently resolves the issue. Ignoring this fault can lead to increased pollution, higher fuel consumption, and potentially damage other components like the catalytic converter over time. A regular inspection of the EGR system and its connectors during routine maintenance can help prevent this code from appearing and keep your Chrysler in perfect working order.