Not my cup of cake
At the launch of the New Mclaren supercar Ron Dennis put forward the theory that Vettel's loss of pace and then subsequent recovery in the last 3rd of the race in Bahrain could have been due to him running low on fuel:
Given Mclaren build the ECU's you would assume Ron knows fairly well how these things work. RD goes on to suggest that perhaps the fuel tank on the RB6 isn't big enough to cope with the demand of the Renault engine; which ties in nicely with Red Bull and Renault's demands to do more development work on their shared engine."The lap times dropped so rapidly that one can imagine the electronic control unit (ECU) switching to a conservative programme to save fuel," Dennis is quoted as saying in a report of the Cologne newspaper Express.