CUUA engine faults.

The EGR cooler cools the recirculated exhaust gas before it enters the intake again, and coolant flows through it while it does so. The temperature difference between the two sides is large, so the wall can crack or the gasket can let through, and then the coolant reaches the exhaust or the intake side. This leaves no puddle under the car and the place of the leak is not visible from outside: the coolant evaporates and the level drops slowly, over weeks. The accompanying signs are whitish smoke, a rising coolant temperature, raised pressure in the cooling system and a sweetish smell. If it goes on for months the cylinder head can be damaged too, because the cooling gradually gets worse. On the EA189 engines the fault code P2425 usually comes with it. The problem is reported above 100,000 km, and replacing the cooler costs 600 to 1,500 euro.

The internal springs of the flywheel tire, and the two discs knock against each other. The signs are a rattling or knocking from the bellhousing at idle and when releasing the clutch pedal, and vibration through the floor. If the clutch slips without a burnt smell, that also points to the flywheel. It is worth replacing in time: a disintegrated flywheel can destroy the bellhousing too. At a clutch replacement the two go together anyway.