Which Octane to use; 91 or 95 (2006 Sylphy 2.0 Litre)

[Komata]

I am currently having a debate with my son as to the best fuel to use for my 'new' 2.0 litre 2006 Sylphy.

 

In my 2.0 'Primera I always used 91 Octane, but was told by the dealer from whom I purchased the 'Sylphy, that I should ONLY use 95 Octane, and that 91 was 'bad' for the motor (although 'bad' wasn't defined).

 

My son disagrees, and says that 91 will work just as well as 95 (and be cheaper too).

 

Not wishing to 'wreck' anything, and in the absence of an Owners Handbook, who is correct? 

 

Thanks in advance.

 

Komata

 

 

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