How to Install Spark Plugs in a Mercedes Benz

1. Open the hood. Your Mercedes Benz may have an engine cover. If so, remove it. Begin by locating and removing the coil packs, which usually cover the spark plugs. Use the appropriate ratchet set by checking the vehicle manual if needed, then gently loosen the coil pack. Pull up on the coil pack and turn slightly until it comes completely free from the engine. Disconnect any wires or wire harness if necessary. Notice the spark plug directly underneath.
2. Loosen the old spark plug using the same ratchet. Use tool extensions and/or spark plug sockets if needed. Grab the spark plug with a free hand and gently pull until it is free from the engine. If the plugs have not been changed for some time, rust or fusion may have occurred, so be cautious of this and do not pull too hard. You want to avoid damage and not leave behind any pieces of the old plug.
3. Take the new spark plug and gap it using the gapping tool set after checking the automobile manual for exact gap settings. Now, install the newly gapped spark plug into the open spot from where the old plug was removed. Use the ratchet and extensions needed to firmly tighten the new spark plug securely into place. Replace the coil pack and any wiring that was removed.
4. Repeat these three steps until all spark plugs are replaced. Replace the coil packs and any disconnected wires. Reconnect the battery then start your car to make sure the plugs have been installed correctly.