Hey guys, ive got a bit of an unusual one here.

In new zealand we have 91 and 96 grade fuels same as in australia. Premium is 96 obviously - so this is what Ive been running in my car.

However with the price of petrol going up, I tried regular 91.

With 96, the car smells like rotten eggs when driven a bit harder than ussual, and stumbles slightly when cold (nothing that would cause concern).

However with 91 the car doesnt ping, it has more power and is more responsive and it doesnt smell of rotten eggs.

Why? These cars are meant to run on 96.