How to Tune a Mercedes E Class

Instructions
1. Treat the motor by using a special treatment to remove varnish and carbon deposits which may have developed within the engine's cylinders and valves. Typically, you would add one ounce of treatment to each gallon of fuel that would then be added to the fuel tank. Repeat as necessary. Use premium fuel at least once after treatment.
2. Change the Mercedes E-Class spark plugs. Open the hood and remove the engine cover. Locate and remove the coil packs which cover the spark plugs. Use a ratchet and socket set to loosen the coil pack if necessary. By pulling up the coil pack, you will be able to free it from the engine to discover the spark plugs. Disconnect any wires if necessary. Pull the spark plugs out of its sockets and remove them gently from the engine area. Be sure to remove the entire plug. Take the new spark plug and install in the open location. Tighten with socket and ratchet, replace the coil pack and tighten. Start the engine and if it is running smoothly, proceed to the next step. If idling roughly, check each spark plug wire to ensure proper connection and tightness.
3. Replace the air filter. Remove the air intake tubes on the left and right side of the vehicle and then remove the air filter's housing. On the underside of the housing are two screws that must be removed so that the air filter may be swapped out with a new one. After placing the new air filter within the housing, install and tighten the screw. Put the housing back in place and reattach the air intake tubes.
4. Change the oil and oil filter. Locate the oil filter cap on the right side of the engine and in front of the oil cap. Turn the oil filter cap counterclockwise until removed. Remove the oil filter assembly to pull the filter out. Replace with a new filter. Raise the driver side of your Mercedes E-Class with a jack and place jack stands beneath the frame for added stability. Locate the plastic cover of the oil tank underneath the vehicle and pull the drain plug to drain the oil. After the oil has been drained, reattach the drain plug and then pour about 8.5 quarts of fresh synthetic oil into the oil reservoir.
5. Change the coolant. Loosen the drain plug under the radiator and drain the coolant. Reattach the drain plug. Fill the radiator with pure water and then run the engine until that water has warmed. Drain the water out of the radiator and refill it with a 30 to 50 percent coolant mixture designed for your E-Class.
6. Replace the transmission fluid and filter. Locate the drain bolt underneath the car's transmission and remove to drain the fluid. Remove the six bolts surrounding the transmission body holding the transmission pan in place. Remove the pan to reveal the valve and filter body assembly. Do not touch the valve body or use a rag on it. After the fluid has drained, install a new filter by placing it over the valve and filter body assembly and fastening the six bolts along the exterior. Refill the transmission with fresh fluid.