But he believed they had been too "trigger-happy" by raising petrol by 3c a litre at about noon on each of the following two days, in rapid response to overnight commodity price rises.
An exception has been industry minnow Gull, which limited itself to two price rises amounting to 7c a litre on Monday and Wednesday and indicated yesterday there would be no further increase until at least tomorrow.
Managing director Dave Bodger said that was despite a rise in the price of refined Singapore gasoline, which he imports, on Wednesday night.
Asked about an 8.7 per cent fall in the price of US benchmark crude oil early yesterday, to US$48.45c ($65.54c) a barrel in New York, he said: "That's awesome news for motorists. If Singapore and refined prices reflect that tonight it would be unlikely we'dbe moving up."
He was more guarded about chances of an early retail price cut, but said the average at the 45 North Island petrol stations controlled by Gull was 14c below the standard industry rate.
Gull's prices for 91-octane petrol ranged from 163.9c to 173.9c in Auckland yesterday. Its lowest was 162.9c in Whangarei.
Z Energy spokesman Jonathan Hill said about 70 of his company's sites were discounting their prices below the standard industry rate.
"Clearly we hope we're going to head back down and this has been a blip."
Going up
Standard main centre prices of 91-octane petrol per litre
• October 10, 2014: 221.9c
• Sunday, February 1: 172.9c
• Monday: 176.9c
• Tuesday 179.9c
• Yesterday: 182.9c
BP's Jonty Mills said the weaker dollar had fuelled a need to raise pump prices in larger increments than the frequent cuts enjoyed by motorists since October.