For about a year, noticed that the pricing many Caltex service stations set between their 91 octane and 95 octane products has somehow diverged percentage wise from about 5% to about 15%. I did inquire with Caltex New Zealand as to the reason why the gap has widened to the extent that is has, though it appears they’ve palmed off the responsibility to individual service stations, while the said stations have pushed it back on to Head Office.

Anyway, in the interim, I shall exercise my responsibility as a consumer (as I did to Two Degrees Mobile) and go to their sister brand, Z Energy or to Mobil where both brands often have their 95 RON petrol priced about 15-21c cheaper than Caltex.

It also does bring in to question how often Caltex turns over their 95 product as well as I have noticed my engine recently appears to behave rather differently between different tank fulls of the same Caltex product. For example, one tank full of Caltex 95 RON gasoline may feel quite perky, while with another tank full from the next Caltex station, my engine may instead feel surprisingly sluggish with me needing to noticeably mash the accelerator a bit harder to get up hills.

So far with Z Energy, all my tank fulls have felt a bit more consistent and dare I say it, smoother running with a small increase in fuel economy (according to my written logs) overall. I wouldn’t be surprised to learn it’s because Z Energy turn their 95 RON fuel over more frequently.