Verstappen faced a late drama ahead of the Hungaroring race when the power unit he had been scheduled to run had to be replaced on Saturday night after Honda detected problems with it.
The engine, which was the one that had suffered a 51G impact in his British Grand Prix accident, had run without problems in Friday practice at the Hungaroring and looked to be okay through Saturday.
However, while nothing untoward was showing up on the data, a physical inspection of it after qualifying revealed a crack – and it was clear it would be too much of a risk to try to keep it in for the race.
While the state of the problem does appear to be terminal for the power unit, which is Verstappen’s second of the season, Honda wants to give it another close up examination to see if there is any chance of it being saved.
Honda F1 technical director Toyoharu Tanabe said: “We will send it back to Sakura [Honda’s R&D facilities in Japan] to check the situation of the crack and its position. We can then work out what will happen in the future, and consider whether it can be repaired.
“Since it is not possible to replace parts, we will consider whether it can be repaired from the outside. The result of that will determine whether or not it can be used in the future. I don’t know, but I feel that it’s a pretty difficult situation.”
Tanabe revealed how Honda uncovered the cracks after qualifying, with them not having been noticed before.
“After qualifying, the car came back, we removed the cowling, removed the cover, and found them while checking the PU,” he said.
“We had checked the same thing before the qualifying, but there was nothing wrong with it. However, when we checked it after qualifying, there were cracks and the oil was seeping out. There was no impact on the data or performance so it was not a part that appears in the data.”
As well as Verstappen’s cracked engine being returned to Japan, Tanabe says that Sergio Perez’s second power unit will also need checking to see if it can be used again after it failed in the wake of the first lap crash in Hungary.
“There are some abnormalities in the data, so I feel that it may be quite difficult to continue using it in the future,” added Tanabe.