The VW group's small-car segment remains a bestseller in Germany. Whether Polo, Fabia or Ibiza, these cars are popular with new drivers and for city driving.
Unfortunately, a far-reaching problem lies behind the nippy little runabout. In the Polo 6R and 9N, Fox, Ibiza III and IV and Fabia I and II generations, the VAG group relied on small 1.2-litre three-cylinder engines. Engines fitted here included the CGP, AWY, AZQ, BME, BMD, BBM, CHF and BZG.
The Problem: The Timing Chain
The problem lies in how the engine components are driven: by a timing chain, which makes the CGP engine, for example, vulnerable to failure.
Frequent short journeys in particular mean the engine never warms up to operating temperature. As a result, the oil pressure is too high because the oil is still too viscous, and the components are over-supplied. This is fatal for the chain tensioner: it is pushed sharply forward when the engine starts and cannot then retract properly.
The timing chain is therefore no longer guided correctly, and the shape of the chain changes over time. After a certain mileage the point is reached at which the chain is no longer guided on the correct sprockets: your timing chain jumps.
The Chain Reaction Inside the Engine
This triggers a chain reaction: the inlet and exhaust valves no longer open and close at the right moment. They strike the pistons and bend or break off. Either outcome causes catastrophic engine damage, since in the worst case the entire combustion chamber is destroyed.
How Do You Recognise a Faulty Timing Chain?
We recommend having the timing chain checked every 45,000 kilometres. But how can you as a driver tell whether a check may already be too late?
- Rattling after starting the engine is the most obvious sign
- A brief rattle is generally not yet serious – but you should still consider having it checked
- If the engine rattles for several seconds after starting, a check is essential
In individual cases it may be possible to replace only the timing chain. Please also read our article Avoiding Engine Damage.
Further Problems with the 1.2 Three-Cylinder Engine
Have you noticed increased oil consumption on your Polo 9N 1.2 along with a loss of performance? The cylinder liners also suffer from wear: the honing wears away over time, causing increased oil consumption and, eventually, a noticeable loss of power.
What We Can Do for Your Small Car
In the event of engine damage we can supply a fully overhauled replacement engine for the 1.2 three-cylinder units – either fitted in our master workshop including nationwide vehicle collection, or despatched to your own workshop.
Does your Polo, Fabia or Ibiza rattle on starting? Send us the VIN or engine code – we will gladly prepare a quotation.
