56K miles. Full service with fully synthetic oil. Gets average 60+ mpg.
Except for an undiagnosed engine rattle but ONLY under acceleration.
Worse when engine cold but improves as engine warms up but doesn't entirely silence.
Do I have a problem pending?

 

Full service 3k ago. Fully synthetic.

 

Thought these were pretty bullet proof but are known to use a bit of oil, being a 3 cylinder they do tend to be a bit lumpy, especially at idle. I can only imagine it's timing chain related as there isn't much else to them, we have a 107 with the same engine on 127k. Assume its the Toyota Petrol engine and not the PSA diesel.

 

Yes it's a petrol engine and so far, in nearly a year, (it's a 13 reg), hasn't used any measurable oil since it's recent service.
I get your suggestion on the timing chain but why does it rattle on accel and worse when engine is cold.
I get 64mpg (at 70mph) on motorway driving, 58+ on rural driving so whatever it is hasn't affected efficiency.

 

In the 50k weve owned ours, other than servicing, brakes, a back box and a water pump I've not delved any further into it mechanically so not sure what the timing chain setup is like, I know a full service only takes half an hour with 2 tools, 4 if you do the plugs.