The South Australia state regulator fined six petrol stations nearly $20,000 for price breaches.
The inspectorate ran checks and found issues mainly around pricing rules.
Customers were encouraged to call in if they spotted price inflation at pumps during the inspection.
No company identifiers or location details were released yet.
Total fines total after recent patrol visits.
In Greater Western Sydney, Blacktown motorists now spend extra for fuel than surrounding districts.
Regular pump checks reveal the area’s prices sit above other nearby spots.
The gap means drivers there spend more per litre each time they fill up.
The gap has widened than what regulators anticipate in usual regional swings.