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Replacing Spark Plugs and Cleaning Leads

Model: Mercedes CLS C219, MK 1 - Years 2004-2010
Part: Spark plugs

Gently remove the plastic cover protecting the engine by lifting it upwards after disconnecting the air hoses attached to it. To avoid mixing up the leads, disconnect only the first spark plug. Using a ratchet spanner, unscrew the retaining screw of the coil connected to the first spark plugs and pull the connection cap upwards. Check the number on the coil and the one on the caps. At the bottom of the well is the first spark plug. Before proceeding with removal, thoroughly clean the wells with compressed air to eliminate any dirt that could fall into the combustion chamber. Using the appropriate spark plug socket, which has a rubber gripping device, gently insert it onto the spark plug head and unscrew it. Be careful not to drop foreign objects into the well. Replace the spark plug with one of the same model, carefully inserting it into the well, always using the appropriate socket and turning it gently to ensure it screws in correctly. If you encounter resistance, remove it and try again. The spark plugs should be tightened with a torque wrench; if you do not have one, tighten without overdoing it. Repeat the same operation with the other spark plugs.
Use an anti-oxidant spray to clean the leads and contacts of the caps before reassembling them.

Updated on 3 February 2026 by ScegliAuto

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