Ad description
The website fuelcat.co.uk, seen in May 2025, a company which sold fuel catalysts intended to be added to a vehicle’s fuel tank or fuel lines, included the text “What is Fuel Cat? […] Made from an amalgam of specific metals, it acts like a permanent octane booster, a combustion enhancer and combustion chamber carbon deposits cleaner. When the fuel flows through FUEL CAT fuel catalyst, a chemical reaction instantly takes place. The shape, temperature and speed of the burn are transformed, making combustion more complete and even, contributing to greater engine efficiency”.
Issue
The complainant challenged whether the claim that the product could improve engine efficiency was misleading and could be substantiated.
Response
Formulapower/fuelcat Ltd t/a Fuel Cat said that they had been manufacturing their catalyst since 1989 and had never received any complaints about their product. They said that they primarily sold their product to owners of old and classic cars.
Fuel Cat said they held evidence from tests showing emission reductions but confirmed those were not new and had been submitted to the ASA previously. Fuel Cat said those tests showed reductions in emissions and supported the claimed effects of the catalyst, although they acknowledged the evidence was historic.
Assessment
Upheld
The ASA considered that consumers were likely to understand the claim, “When the fuel flows through FUEL CAT fuel catalyst, a chemical reaction instantly takes place […] contributing to greater engine efficiency” to mean that the product could improve the engine and fuel efficiency of a vehicle when added to the fuel tank or fuel lines. We considered that this was an objective claim which required robust substantiation based on independent testing. We considered that we would need to see evidence that the results of the tests provided would be applicable to all or most vehicles in which the product might be used.
We assessed the tests previously provided by Fuel Cat. We noted that the material dated from 1992 to 1997 and included tests for fuel consumption, engine performance and emissions. We considered that there were several limitations in the evidence provided. For example, the tests were carried out on a small sample size of individual vehicles or engines without evidence that the results would apply to all or most vehicles. Some tests included statements that the results applied only to the vehicle tested or to those of similar technology. It was also unclear in some cases whether the product tested was the Fuel Cat product as currently sold. We also understood that some of the tests were ongoing or incomplete and did not provide final results.
We further considered that the tests were unlikely to be representative of vehicles and fuel currently in use, as they were carried out over 25 years ago. We had not seen evidence that the results would be relevant to modern vehicles.
Because of the limitations of the tests provided, we considered that the evidence was not sufficiently robust to demonstrate that the Fuel Cat product could improve engine efficiency. We therefore concluded that the claim had not been substantiated and was misleading.
The ad breached CAP Code (Edition 12) rules 3.1 (Misleading advertising) and 3.7 (Substantiation).
Action
The ad must not appear again in its current form. We told Formulapower/fuelcat Ltd t/a Fuel Cat not to claim that their products could improve engine efficiency, unless they held adequate evidence to substantiate that claim.
