Nico Hulkenberg clarified that the problem that sidelined him from the season-opening Australian Grand Prix last weekend was so severe that it would have been simply unsafe for him to run it.
Sauber pulled out the German’s car just ahead of the race on Sunday due to a fuel-system failure, with signs of damage appearing only two hours before the scheduled start, which meant the issue wasn’t present during qualifying earlier in the day.
“I basically came back from the drivers’ parade and was told that there is a grave problem with the car,” Hulkenberg told the official Formula 1 website. “I ran into the garage to have a look and that was where I understood what they were talking about.
“The engine was out - the whole car was apart. I was shocked. What had happened? When they started to fill the car for the race, suddenly there was that issue with the tank,” he pointed out.
The 25-year-old explained that "a vacuum developed inside the (fuel) tank, which did some damage to it".
"A tank is somewhat comparable to something like a Tetra Pak. When there is a vacuum inside and you fill in liquid it will swell - and eventually explode," he added.
Sauber had sent the car back to its factory at Hinwil for a full examination with Hulkenberg to race in Malaysia with a new chassis, adding that measures have now been taken “to make sure it never happens again.”