However, Sasol said the pills were nothing but a scam.
Speaking on eNCA, Sasol's senior technical adviser for retail and commercial Adrian Velaers said the company tested four types of systems using the pills and in each case there was less than a 1% difference in fuel efficiency.
“These pills claim that they can save you 10% to 30% in fuel consumption, but they did absolutely nothing,” said Velaers.
He warned the pills could have a detrimental effect on vehicles' engines.
“Things you put in your tank can damage your fuel gauge, airflow and turbo. These sort of things would not be covered by your warrantee,” he said.
The Automobile Association (AA) also warned of the risks using “fuel saving” pills.
Speaking to SABC News, AA spokesperson Layton Beard cautioned motorists against the use of “fuel saving” chemicals or pills in their vehicles.
“These pills have not been approved by the AA or been through any chemical analysis. It's very dangerous, in our opinion, to be using these pills and devices that have not been tested and approved because the long-term damage to the engine is still unknown,” said Beard.
Previously, the AA warned of the risks that could happen when using “fuel saving” pills.
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