Optimum petrol purchase time to 'remain a mystery'

Australian motorists who are struggling with their personal finances could be among those disheartened by new research into cheap petrol prices.

Recently, many drivers have formed long queues on Monday morning in the belief that this is the best time to get value for money at the pumps.

However, a recent study has revealed that the optimum petrol purchasing time is set to remain a mystery, the Daily Telegraph reported.

Last year a number of stations ran "Cheap Tuesday" promotions for customers to take advantage of lower rates.

The point at which petrol is cheaper has however moved through each day of the week in recent months.

Fuel and oil provider Caltex, told the newspaper that the cheap point is unpredictable and is solely driven by competition.

Julian Segal, the firm's chief executive officer, said: "We have done significant work with economists from Australia and also from other countries that experience the weekly cycle.

"What that research clearly indicates is that … the existence of a weekly cycle is an indication of very, very fierce competition in the market."