Should I fit a fuel saving device?

I have read about a device that plugs into the car under the steering column and claims to reduce fuel consumption by about 35 per cent. Is the claim valid? Is it safe to use? Seems strange that the technology is not built in to all cars. Should I buy one?

Asked on 15 August 2022 by Geoffrey Bernstein

Answered by Lawrence Allan

We have seen no scientific evidence that demonstrates the claims of these products. A device that plugs into the OBD port is not capable of changing the car's fuel consumption by such a drastic amount. Even a professionally tuned and installed ECU remap would only achieve a 10 per cent to 15 per cent increase, so we'd be wary.

Tags: fuel economy fuel

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