Wind tunnels are still causing headaches for Ferrari.
The fabled team moved its entire aerodynamic testing programme to the Toyota facility in Cologne, after concluding that its own wind tunnel at Maranello needed to be rebuilt because it was not producing reliable data.
But Germany's Auto Motor und Sport claims that, as development progress with the 2013 Ferrari car seemed to stall recently, the data produced by the Toyota tunnel has also been raising eyebrows.
"It's a difficult situation," admitted Simone Resta, the project chief for the F138 car.
"Despite having our own wind tunnel, we are still struggling and are obliged to work abroad," he is quoted by Italian newspaper La Stampa correspondent Stefano Mancini.
"We hope to resolve it by the end of summer," added Resta.