vinkodex.
Known fault

FSI direct injection: intake valve coking

It does not show up on every car. Check before you buy.

expensive

severity

not available

mileage

2

sources

2 sources next to the write-up.

The fault

How you spot it

With direct injection the fuel does not wash the intake valves: the petrol goes into the cylinder, not behind the valve. The oil mist and soot arriving through the EGR and the crankcase ventilation therefore build up on the valve stem and head, and from 80,000 to 100,000 km they restrict the flow. Symptoms are hesitation, loss of power, a rough cold start and misfire. It is not a part failure: it is a consequence of the design, and therefore it comes back. Cleaning (walnut or dry ice blasting) helps for a few tens of thousands of kilometres.

Which model

Who it affects

The card opens the generation, the engine or the transmission.

Engines and transmissions

Checklist

FSI direct injection: intake valve coking

What you would check for this fault. Take it to the car.

Before you buy

Checklist

What you tick stays on this device only.

vinkodex.com · Before you buy it, see what can go wrong.

Sources

How we know

Information, not an expert opinion

We write the descriptions, and we put the source next to them. A person reviews them before they go out. They are still information, not a technical expert opinion.

  • A fault on the list does not mean the car you are looking at has it.
  • A fault missing from the list does not mean the model is fault-free. Write-ups are made model by model. Not all of them are done.
  • You decide whether to buy. This is no substitute for an inspection. That needs a workshop and a history check.
Details in the terms