Sep.10 (GMM) Mark Webber's alternator survived the Italian Grand Prix because it was an "older" specification.
That is the claim of Red Bull's Dr Helmut Marko, after reigning world champion Sebastian Vettel on Sunday suffered a repeat of his Saturday morning failure and failed to finish at Monza.
"The part was from the latest specification (of alternator) that came after the similar failure in Valencia," Marko is quoted by Salzburger Nachrichten.
"Webber had an alternator from an older specification that had no problem," said the Austrian.
Germany's Auto Motor und Sport said engine supplier Renault, whose supply partner for the alternator is Magneti Marelli, is treating the problem as a priority.
"Since 2011 we have changed virtually nothing," said Renault's baffled Remi Taffin.
One glimmer of hope is that the Renault alternator used by Lotus' Jerome d'Ambrosio at Monza was showing early signs of failure, which could be useful for getting to the bottom of the mystery.
Arguably the bigger problem for Red Bull, however, is the recent lack of pace.
Former Toro Rosso driver Jaime Alguersuari said Monza was "the (team's) worst performance since 2008".
And yet another problem on Sunday was Vettel's penalty for driving Fernando Alonso off the track, even though a similar incident at Curva Grande a year ago was ignored by the stewards.
Was the FIA giving Ferrari a helping-hand at Monza on Sunday?
"I think not," Vettel, dismissing the conspiracy, told Bild newspaper.