The roadbook error came at kilometre 158 of stage 7, a 412km loop which started and finished in Al Duawadimi, and was enough to take the leaders off course.
Losing precious time, they drove aimlessly in the desert until an organisation helicopter came to put the cars back on the right track.
“We were there for 50 minutes, 50 minutes of going round in circles,” said Belgian driver Guillaume de Mevius, who was among the first to arrive at the faulty mark in his Mini.
“We were crossing paths with everyone who was turning round, trying to get to the same place as us but which we’d already tried.”
As a result, the organisers had to erase the times on a 20-kilometre section of the special although there was still confusion over the remainder of the course because of the order in which the cars had set out.
The incident prompted stinging criticism of the organisers.
“When you want to do the roadbook, do it well,” said Qatar’s five-time winner Nasser al-Attiyah, driving a Dacia, at the finish.
“You have to check it many, many times because this was a disaster. It was a big risk.”
Brazilian Lucas Moraes of Toyota emerged from the confusion as the day’s stage winner, finishing 7min 41sec ahead of Swede Mattias Ekstrom with American Mitchell Guthrie at 9min 28sec, both in Fords.
“Nice to win one more stage in the Dakar, these things are really hard to get,” said Moraes.
“I think maybe tomorrow it’s going to be just like this one today and then we’re going to start reaching the Empty Quarter.”
In the overall standings, South African leader Henk Lategan in a Toyota has a lead of just 21 seconds over Saudi Arabia’s Yazeed al-Rajhi. Ekstrom is third at 10min 25sec.
The car category also saw the withdrawal for “medical reasons” of the duo of Toby Price and Sam Sunderland of Overdrive. The double Dakar winners in the bike category had teamed up this year in the cars.
‘Pretty fast’ Sanders
Daniel Sanders underlined his dominance on the bikes, which were not affected by the roadbook error, with his fifth stage win of this year’s race.
The 30-year-old Australian (KTM) finished 3min 36sec ahead of 19-year-old Spaniard Edgar Canet.
“It was pretty fast, very fast,” said Sanders.