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Diagnosis and Repair of the Secondary Air Injection System Fault

Model: Volkswagen Golf Golf IV, MK 4, Golf 4 - Years 1997-2003
Part: Checks and maintenance

The secondary air injection system reduces harmful emissions by allowing further combustion of the engine's exhaust gases, injecting an oxidiser to aid in breaking down these gases. Using diagnostic software, connect to the vehicle's port and compare the manufacturer's data with the measurements obtained: once anomalies are detected, proceed with a physical analysis of the system. Create a vacuum from a valve in the circuit and check for leaks. If the vacuum is not maintained, it indicates a leak in the circuit, and you should search for faults in the pipes. Once the damaged pipes are found and replaced, conduct a new check using the software: if the obtained data matches the declared values, the problem is resolved.

Updated on 8 February 2026 by ScegliAuto

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How to Open a Stuck Boot on the Peugeot 407?

On the Peugeot 407, the boot may become stuck, possibly due to a problem with the control button or the lock actuator. In such cases, you can perform an emergency opening by following the simple procedure shown in this tutorial. First, open the rear doors, then lower the seat back by operating the release lever. Next, go inside the boot, locate the lock, and manually operate it using a flathead screwdriver. The boot will then be free to open.

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