What is the function of the engine mounts in Citroën C3 and C4 models? What are the symptoms that indicate a fault, and which is the most problematic?

You Cushions (or mounts) for the engine and transmission are rubber and metal parts whose main function is isolate the vibration generated by the running engine from the vehicle’s chassis and body. They also keep the engine/transmission assembly in the correct position, especially during acceleration and braking.

• Symptoms of Failure:
  1. Excessive Vibration: Strong vibration felt in the steering wheel and cabin, especially at idle or during light acceleration.
  2. “Dry Knock” noise: A metallic knocking noise when engaging gear (especially reverse or first) or when going over potholes/speed bumps.
  3. Excessive Engine Movement: When you open the hood and accelerate, the engine moves much more than normal.
• Chronic (Hydraulic) Cushion: In many models, the upper cushion (right side, near the battery) is of the type… hydraulicThis cushion, filled with a fluid for better vibration absorption, tends to burst, leaking the fluid and losing its damping capacity. It is usually the first to fail and the most expensive to replace.

Solution: It is crucial to replace faulty engine mounts immediately. Failure of the mounts can cause excessive stress on the exhaust systems, hoses, and even the drive shaft (constant velocity joint) and transmission assembly, leading to more expensive repairs. Replacement with good quality parts is recommended to ensure durability and comfort.