Ask an expert
Read your article on being wary on fuel saving devices and thought you might like to have a look at this one and let me know what you think.
The address is www.tunit.com
From the "Ask Jack" archive - 14 December 2009
Thanks for the feedback on the AA's recent fuel saving devices article.
From what I know about that particular product it is more performance oriented.
They can re-chip a computer to enhanced power which basically takes an engine outside a manufactures built in cushion or comfort zones.
Manufacturers always build in these comfort zones rather than have engines on the limit at certain points and to ensure a smooth overall driving performance.
When an engine is re-chipped you will often find gains in some areas and losses in others depending on what you want to achieve.
I don't believe you could successfully re-chip a computer to improve fuel economy and retain good overall performance. The manufactures work very hard to get that balance spot-on in my opinion.