EA111 1.2 3-cyl MPI (6V: AWY/BMD/BBM/CHFA; 12V: AZQ/BME/BZG/CGPA/CGPB/CJLB)

Rattle from the chain on cold start, rough running, engine warning light with camshaft/crankshaft correlation codes

The best-known fault of this engine. German buyer guides say the chain stretches and can cause major engine damage and advise avoiding the 1.2; Auto Bild reported chain and tensioner failures on the Polo 9N and carwiki says the chain can jump on cars up to the end of 2005. An engine database gives the chain a life of about 50,000 km on early engines and says it can jump after the car is parked in gear because of the hydraulic tensioner. French owners of the Polo V 1.2 also name the timing chain as the most reported fault. VW later sold a modified chain kit. Replace chain, tensioner and guides together. Cost not sourced.

Misfire on one cylinder, low compression on test, rough idle

Valve burn-out and falling compression are common above about 100,000 km according to an engine database. A German buyer guide calls it a design fault: the catalytic converter sits too close to the cylinder head, so hot exhaust gas can damage the head and valves, and the only cure is a new head with valves. French owner reviews report valve and cylinder head faults. Cost not sourced.

Misfire, flashing engine light, loss of power

Coils failed on early cars (L'argus: up to 2002) and again on later ones (Gebrauchtwagenberater: Polo 6R 2009-2010; carwiki: pencil coils from 2005). Each coil is replaced on its own.

Hunting or uneven idle, hesitation when pulling away

Deposits in the throttle body and crankcase ventilation make the idle speed float. Cleaning the throttle body and re-adapting it usually cures it.