DEFECTIVE E10 petrol is reportedly responsible for up to 20 cars breaking down on a major Sydney motorway on Thursday morning.
In a statement Caltex said the fuel came from one service station.
It was reported that affected drivers managed to pull into the motorway breakdown lane and their vehicles were towed away a short time later.
Caltex said it shut down the pumps for that product as soon as the issue was known.
"The problem is isolated to the E10 product at this site only - there are no other products or sites affected," Caltex media spokesman Sam Collyer said.
"Caltex is sorry for the inconvenience to customers and will fully reimburse them for any out-of-pocket expenses incurred as a result of the fuel."