How To Check & Replace Your Timing Chain...Ford Mondeo Mk5 2L Diesel

This is a particular bad case of a timing chain that is about to break as the tensioner nylon guides have all broken and worn away.
Apart from putting a pick into the oil filler cap hole to prod the timing chain to see if it is loose you can also put a piece of paper over the oil filler hole with the engine running...if the paper gets soaked in oil very quickly there is a good chance you will need a new timing chain and tensioner.