Motorists have a small window to fill up cheaply as many cities hit their first new petrol cycle after fuel excise was reinstated.
Some retailers are charging more than $2.10 a litre across the major capital cities but others are yet to lift prices, Compare the Market data shows.
The surge in fuel prices follows the return of the excise after it was temporarily halved as a cost-of-living relief measure when the war in Ukraine sent fuel prices skyrocketing earlier in the year.
So far, the return of the full rate of tax has failed to show up at the pump but Compare the Market energy expert Chris Ford said the start of a new fuel cycle means prices would now start climbing.
He said new fuel price cycles started in Sydney and Brisbane on Friday.
"We know that fuel prices fluctuate in regular cycles and commuters will see the biggest difference between the cheapest and the most expensive at the start of the cycle, when prices are climbing," Mr Ford said.
In Sydney, Melbourne, Brisbane and Adelaide, a 50-cent gap now exists between the cheapest and most expensive fuel.
Based on a weekly average, fuel prices only rose by a modest 1.4 cents last week, according to the Australian Institute of Petroleum's fuel report.
The average for the week was likely pulled down by low prices early in the week.
Mr Ford said retailers were only starting to hike prices over the weekend in most cities.
But the average diesel price has surged to near record highs, with the national average lifting by 11.2 cents last week to hit $2.33 a litre.
Wholesale fuel prices have remained fairly steady but the Organisation of the Petroleum Exporting Countries' decision to cut production is keeping upward pressure on petrol prices.
"Fuel prices skyrocketed earlier this year due to fuel supply chain issues caused by the COVID pandemic, the war in Ukraine and supply shortages, but it's OPEC's latest decision to cut oil production that will keep prices high now," Mr Ford said.
CommSec economist Craig James said fears of a global recession were simultaneously putting downward pressure on prices.
"Also, the zero COVID policy in China continues to restrain the economy and thus oil demand," he said.
Higher costs for fuel, labour and raw materials also led to a contraction in Australian business activity in October as measured by S&P Global's purchasing managers' index.
Both the manufacturing and services PMIs fell into sub-50 territory, which indicates a contraction, for the first time since January.
"Overall business confidence, meanwhile, continued to trend lower in October to the weakest since the height of the COVID pandemic in April 2020, which is not a positive sign for the Australian economy," S&P Global economists said.
Australia's longer-term growth outlook has also been downgraded, although Treasury has boosted its growth forecasts for 2022/23 by a quarter of a percentage point from predictions made in July.
It comes as internal RBA research says property prices could fall by as much as 20 per cent by the end of 2024 amid higher interest rates and a slowing economy.
The country's slowdown in domestic growth is expected to worsen in 2023/24, with Treasury cutting its forecast for growth by half a percentage point from July projections.
