buying a 2012 s60 t5
 

I'm seeing a vehicle like this to buy, s60 2011/2012, 2.0 t5
engine b4204t7
vin bc2103026
it's well maintained, the only thing is that the check engine light is on.

the owner said that this is a common problem in this model, because of the quality of our petrol (I live in Brazil)

I would like to know if this really applies.
and also what advise me to look specifically at this model, some recommendation?

thank you