The four problems that are common on the MK4 R32 are timing chain and tensioner failure, radiator fan failure, thermostat and cooling hose cracks, and MAF sensor issues. The majority of the problems are cooling system related which is important due to problems that can occur with the sensitive timing chain if the engine overheats. However, with proper maintenance and oil changes the VR6 engine used in the R32 is actually very reliable. As these engines age they will require more maintenance with basic items like gaskets, pipes, spark plugs, and so on but the engine suffers very few serious problems as long as the timing system is properly maintained.