Mercedes CLA diesel intake manifold flap control issue

Your description mirrors a problem I encountered some time ago on my CLA The loud hissing and power loss do indeed suggest an issue with the intake manifold flap The flap control mechanism is known to be somewhat fragile A malfunctioning flap control can definitely trigger the engine light and lead to the symptoms you describe Have you checked for any error codes using an OBD II scanner The error codes related to the intake manifold flap or intake system would provide further confirmation The actuator arm for the manifold flap can become detached or the sensor could fail Was any diagnostic work performed to pinpoint the intake manifold flap control as the sole cause

I did indeed use an OBD II scanner, and it returned a code indicating a problem with the intake manifold flap However, it did not definitively specify whether the flap itself or the control mechanism was at fault The diagnostic pointed toward the 'intake manifold flap control' as the likely culprit, but I lack the expertise to differentiate between a defective control and a seized flap Is there a method to ascertain which component is failing, the manifold flap or the flap control, without dismantling the entire intake system

Given the error code points towards the intake manifold flap control, and the symptoms you are experiencing, it is more likely the control mechanism itself While a seized flap could cause issues, a faulty control is a more common failure on the CLA Unfortunately, without a more detailed diagnostic procedure, such as physically inspecting the flap and control linkage, it is difficult to be 100% certain I would suggest consulting a qualified mechanic for a thorough assessment They can perform tests on the actuator and linkage to determine if the control is functioning correctly Replacing the entire intake manifold is a significant undertaking, so confirming the flap control as the definitive problem beforehand is prudent Prepare for a workshop visit

I appreciate your insights, which have proven invaluable Following your counsel, I consulted a mechanic who confirmed the intake manifold flap control as the source of the problem The defective control was subsequently replaced, resolving the issue entirely The engine now runs smoothly, the hissing sound has vanished, and the fuel consumption has returned to normal Once again, thank you for sharing your expertise