The watchdog is to spend six weeks gathering information and will investigate whether falling crude oil prices are being reflected in the cost paid at the pumps.  
It will also look into behaviour by supermarkets and oil companies to establish whether they are making trading conditions more difficult for independent fuel retailers, as well as examining the lack of competition at fuel stations in rural areas. The investigation does not concern fuel duty, which is said to make up around 60% of the total cost paid.
The OFT is appealing to “the industry, motoring groups and consumer bodies” to get in touch with information relevant to the cause. A spokesperson for the BVRLA said the organisation had no current plans to submit information but that it was talking to its members to assess what action, if any, they want it to take.  
The Department for Transport has previously suggested that an industry code of conduct should be introduced, in order to implement price reductions at the pumps as quickly as a fortnight after they had been felt in the wholesale market.
Speaking to the BBC, the OFT’s senior director Ann Pope said there would be ramifications for fuel retailers if they were found to be profiting from falls in oil prices.
The findings of the investigation are due to be announced in January. Parties interested in contributing should email roadfuel@oft.gsi.gov.uk by 17 October.