EGR valves of the quality brand VEMO

The recirculation of oxygen-deficient and carbon dioxide-containing exhaust gases displaces the fresh air in the intake manifold and reduces the amount of oxygen of the fresh gases. Thus, the combustion rate decreases. The higher heat capacity of the exhaust gas compared to fresh air lowers the combustion temperature because the existing carbon dioxide absorbs part of the heat of combustion. The exhaust gas recirculation is activated e. g. during idling and partial load operation of warm diesel engines. Depending on the design, the EGR valve is regulated electrically or by vacuum. Further, some EGR valves are having a combined control.

Advantages of VEMO EGR Valves:

✓ all EGR valves including gasket
✓ shock-resistant packaging for safe storage and transportation

    Causes of failure

• heavy soiling (sooting or coking)
• defective in the vacuum control
• defect in the electric control
• internal damage in the engine, thereby possibly increased oil consumption
• defect in the intake area, heavily soiled air filter, defective air mass meter
• improper valve clearance
• unclean combustion
• contamination of electronic components
• possibly incorrect software in the engine control unit
• wrong or burned engine oil

    Consequential damages

• engine is not running smoothly
• the motor control lamp (MIL) lights up
• increased fuel consumption
• incorrect exhaust gas values
• destruction of the exhaust gas control system (particulate filter / oxidation catalyst)
• damage to the engine mechanics due to higher exhaust gas temperatures

Service Information – EGR Valves

When the engine idling is not running smoothly, the vehicle jerks, or the engine goes into emergency mode, it may be that the built-in EGR valve is clogged with oily deposits. As a result, the valve is difficult to move and cannot be fully opened or closed. The reason for this does not usually lie with the EGR valve itself.

The recirculated exhaust gas can contain an increased amount of soot particles, especially in diesel vehicles. This means that after a period of time the performance of the valve can no longer cope with the deposits.

    Tips for remedial action

• In the event of malfunction of the EGR valve, check not only the individual components of the EGR system, but also the surrounding area.
• Do not clean the EGR components; this could damage them.
• Identify the cause of the deposits and remedy the fault.
• If necessary, replace the EGR valve.

Error Message after Replacement

If a new EGR valve was installed and the vehicle behaves as if the valve was not changed, the correct data necessary for operation must be „fine-tuned“ again. This can be done either through a longer test drive or through specific programming by the engine tester, e.g. „Basic setting“.. If any of the above problems arise after installing the EGR valve, then the adjustment range stored in the engine control unit is configured wrongly. With a software update of the engine control unit, the control range can be expanded accordingly, and the problem will thus be solved.

• Signal voltage is out of the tolerance range
• New part with an error message
• Error lamp lights up
• Error code P0400

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