The N47 diesel engine, fitted to many BMW and MINI cars, is known among those who work on these vehicles for a timing system that deserves attention. Not all versions behave in the same way and not every noise means a fault: but a new noise should never be ignored.
Symptoms not to underestimate
- a metallic or rattling noise on a cold start;
- ticking that changes with the engine speed;
- timing errors stored by the control unit;
- irregular starting or an engine that starts with difficulty;
- loss of performance or the engine light on.
Possible causes
The chain may show wear or stretching, but the noise can also come from the tensioning system, the guide rails or other engine components. That is why the sensation of listening alone is not enough to decide.
How the diagnosis is carried out
We start from the symptom described by the customer and a check of the noise. When needed, the error memory is read and the timing parameters are checked; then the technical inspection of the timing system is carried out. Only afterwards is it decided whether to intervene and on which components.
What happens if it is put off
A timing system in poor condition can get worse over time. Acting early makes it possible, in many cases, to limit the extent of the work and the costs.
When to go to the workshop
If you hear a noise that was not there before, especially on start-up, book a check. Describe the model, year and engine and say when the noise appears. You will find more information on the Timing chain page, or request a check.
- diagnostics
- engine
- timing chain
