P0470 Exhaust gas pressure sensor malfunction
OBD2 Error Codes

P0470 Exhaust gas pressure sensor malfunction

27.09.2023 /

P0470 – OBD-II Trouble Code Technical Description

Exhaust gas pressure sensor malfunction

What does the fault code mean P0470?

This general diagnostic trouble code applies to various makes of vehicles, including Ford, Mercedes and Nissan, with different types of engines, including gasoline and diesel, starting in 2005. It is related to exhaust gas pressure and may indicate an electrical or mechanical problem. It can sometimes be accompanied by a P0471 code, which varies in duration and nature of the exhaust pressure sensor failure. Repair steps depend on the manufacturer, fuel type and wire color.

Trouble code P0470 is common across different makes and models of vehicles. It indicates a problem with the exhaust gas pressure sensor and may be due to electrical or mechanical problems. Sometimes it is accompanied by a P0471 code, which varies in the duration of the problem and the nature of the sensor failure. Repair steps may vary depending on manufacturer, fuel type, and wire color.

The Exhaust Back Pressure (EBP) sensor plays an important role in measuring exhaust gas pressure and allows control of the Exhaust Back Pressure Regulator (EPR) by command from the Engine Control Module (ECM).

Typical Exhaust Pressure Gauge:

Relevant Exhaust Pressure Sensor Trouble Codes:

  • P0471 Exhaust Gas Pressure Sensor “A” Circuit Range/Performance
  • P0472 Low signal level in the exhaust gas pressure sensor circuit “A”
  • P0473 Exhaust gas pressure sensor “A” circuit high
  • P0474 Exhaust gas pressure sensor “A” circuit malfunction

Possible reasons

This P0470 code may appear for the following reasons:

  1. There is a blockage in the tube between the exhaust manifold and the pressure sensor.
  2. Problems with the EGR or air intake system, including charge air leaks.
  3. Defective exhaust gas pressure sensor.
  4. Rare: Possible damage to the Powertrain Control Module (PCM), although unlikely.
  5. There is a blockage in the hose connecting the pressure sensor to the exhaust manifold.
  6. The exhaust gas recirculation system is malfunctioning, which can lead to air leaks.
  7. Faulty exhaust backpressure sensor.
  8. Problems with the exhaust backpressure sensor wiring harness, such as opens or short circuits.
  9. Poor electrical connection in the exhaust backpressure sensor circuit.

What are the symptoms of a fault code? P0470?

Symptoms of a P0470 code include:

  1. The Malfunction Indicator Light (MIL), also known as the check engine light, comes on.
  2. Possible appearance of a “Check Engine” light on the control panel with a fault code stored in the ECM memory.
  3. Loss of engine power.
  4. Possibility to disable the exhaust gas pressure regulator.

The P0470 code is considered serious because it can affect the vehicle's handling and performance. But it can easily be eliminated by replacing the defective exhaust gas pressure sensor.

Symptoms of a P0470 code may also include:

  1. The check engine light is constantly on.
  2. Lack of power.
  3. Failure to regenerate the diesel particulate filter, which may result in engine starting failure.

How to diagnose a fault code P0470?

A good way to start diagnosing a P0470 code is to check the Technical Service Bulletin (TSB) for your make of vehicle. The manufacturer may provide a software update (firmware) for the PCM to correct this problem. Next, locate the exhaust gas pressure sensor on your vehicle and disconnect the tube connecting it to the exhaust manifold.

Try clearing this tube of any carbon that may be causing the P0470 code. If the tube is clean, check the connectors and wiring for damage or corrosion. Next, test the 5V power and sensor signal circuits using a digital volt-ohmmeter (DVOM).

Make sure the sensor is properly grounded. If all tests pass, replacement of the exhaust gas pressure sensor may be necessary. If the P0470 code continues to appear, a faulty PCM may also be the cause, but it can only be ruled out after replacing the sensor and performing additional tests.

Diagnostic errors

Potential causes of the P0470 code

When diagnosing a P0470 code, it is important to consider several potential causes that could lead to this code. Below are the main factors to consider:

  1. Blockage in the tube from the exhaust manifold to the pressure sensor: One possible scenario is that carbon builds up in the exhaust system, which can cause a blockage in the tube through which the pressure sensor receives information. This may result in incorrect readings and a P0470 code.
  2. Problems with the exhaust gas recirculation (EGR) system, air intake or charge air leaks: Problems with the exhaust or air supply systems can affect the pressure in the exhaust system and cause the P0470 code. Reliable diagnosis of these components can be an important step.
  3. Exhaust gas pressure sensor malfunction: The exhaust gas pressure sensor itself may fail or produce incorrect signals, resulting in a P0470 code.
  4. Exhaust Back Pressure (EBP) Sensor Problems: The exhaust backpressure sensor is an important component of the engine management system and can be associated with the P0470 code.
  5. Problems with wiring and electrical connections: Damaged wires, corrosion, or improper electrical connections between the sensors and the control system can cause incorrect signals and a P0470 code.

These potential causes of the P0470 code are important to consider during diagnosis and repair to pinpoint and correct the root of the problem.

How serious is the fault code? P0470?

Trouble code P0470 indicates a problem with the exhaust gas pressure sensor or exhaust system pressure. This may affect engine operation, performance and fuel consumption. Although this is not a critical emergency, it is a serious malfunction that can lead to more serious problems if not corrected. It is recommended that you have your engine diagnosed and repaired by a mechanic when the P0470 code appears to prevent engine degradation and maintain engine performance.

What repair will help eliminate the code? P0470?

Resolving the P0470 code involves a number of steps, depending on the identified cause:

  1. Checking Technical Service Bulletins (TSB): Start by looking for information in technical service bulletins, which may contain manufacturer recommendations for solving this problem. The manufacturer may offer PCM flashes/reflashes that may clear the code.
  2. Checking the exhaust pressure sensor: Disconnect the exhaust gas pressure sensor and check for carbon deposits or damage. Clean or replace the sensor if necessary.
  3. Wiring check: Visually inspect the wiring, look for damage, corrosion or broken wires. Disconnect the connectors and clean them if necessary.
  4. Checking the power and signal circuits: Using a digital volt-ohm meter (DVOM), check the 5V power and signal circuits going to the sensor. Make sure the voltage meets the manufacturer's specifications.
  5. Grounding check: Check whether the exhaust gas pressure sensor is properly grounded.
  6. Checking the tube and connections: Carefully check the tube connecting the turbocharger to the intake manifold for leaks.
  7. Clearing errors: Use an OBD-II scanner to clear the P0470 code from the PCM memory. After this, drive the car and check if the error appears again.
  8. Sensor replacement: If the problem cannot be resolved by other methods, replace the exhaust gas pressure sensor.
  9. PCM check: If all of the above steps do not resolve the problem, there may be a problem with the PCM. However, this option should only be considered as a last resort resource.

Remember that diagnosis and repair must be performed by a qualified mechanic or service center to ensure the exact cause and effective resolution of the P0470 code.

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