Have mixed B5 1.8 liter engine with my A4 adding. The engine runs quieter depends on super gas and the fuel consumption was about 2 liters at 100 km (now stands at 7.5 to 8.0 liters). I have previously also changed the spark plugs and engine oil and filter and fuel filter and air filter. Still have Mathy-M added to the engine oil and previously made an engine cleaning with Mathy-C. If anything you should do it completely then it also brings what.
