How to change the oil and filter of the Citroën C4.

On your Citroën C4, the oil change is performed by working both from the engine compartment and from underneath the vehicle. Before starting, warm up the engine to a lukewarm temperature, park on a flat surface, and secure the car on jack stands or a lift. Prepare a large container, gloves, and safety goggles. Open the hood and loosen the oil filler cap to allow for smoother drainage from the oil pan. Go underneath the car, position the container, and unscrew the drain plug: let the oil drain completely until the flow becomes minimal. Clean the area around the drain plug and reattach it without forcing, replacing the washer/gasket if it is worn or a single-use type. At this point, replace the oil filter. Loosen it with the appropriate tool and remove it carefully, as it may contain residual oil. Check that the old gasket is not stuck to the seat and clean the mounting surface. Before installing the new filter, lightly lubricate its gasket with a thin layer of clean oil, then screw it on until it is snug and complete the tightening as specified, avoiding excessive torque. Return to the engine compartment and top up with oil of the correct specification for your C4, pouring gradually and checking the level. Start the engine for a few seconds, turn it off, and wait for the oil to settle; recheck the level and verify from underneath that there are no leaks from the drain plug and the filter. Complete the level if necessary and close the filler cap.