Garages were unclear yesterday if they were supposed to set their petrol pump prices up by 67 cents or 75 cents a litre today.
Asked how much petrol would be going up at midnight, all service station managers could do last night was shrug.
Garage owner Derek Groenwood said: "Shell just phoned me and told me to ignore the price increases I've read in the newspaper or got from the Fuel Retailers Association. They said they are not sure what the price increase is supposed to be yet, and will e-mail me as soon as they know."
The confusion is due to the Minister of Minerals and Energy Buyelwa Sonjica's intervention on Monday to alter this month's fuel price increases her department announced on Friday.
Her revised petrol increase would take 93 octane used inland to R10,56 a litre and 95 octane at the coast to R10,47.
This marks petrol prices clocking four digits for the first time, causing a technical hitch for analog fuel pumps which cannot handle prices over R9,99 a litre.
Petrol stations yesterday were in the dark if the "rounding down rule" to work around this problem announced by the Department of Minerals and Energy still stands.
The price hikes announced on Friday would have seen petrol stations cutting the price by between two cents and three cents a litre to round down.
But Sonjica's decision to delay, including an extra 5,4 cents per litre promised to wholesalers in Friday's announcement, means rounding down now involves cutting the price by six cents to seven cents a litre.
The South African Petroleum Industry Association (Sapia) said it had notified the Department of Minerals and Energy Affairs that the confusion needed to be cleared up before garages could set the new government regulated prices at midnight as required by law.
On Friday, the Department of Minerals and Energy instructed garages to mark analog pumps with "X10" decals.
The department's original statement set the price of inland 93 to R10,62 a litre, but said garages with older pumps should set them to R1,06 and multiply the final bill by 10.
This rounding down rule indicated older pumps would be selling petrol for between two cents and three cents less than newer digital pumps.
But Fuel Retailers Association chief executive officer Peter Morgan said: "The rounded prices must be at all pumps irrespective wither the pumps can read the four digits or not."