The move followed the destruction of the Mexican rookie's car in Malaysia, when an unidentified piece of heavy debris punched a hole in the Ferrari powered C30.
It was initially believed that a loose piece of ballast from a Toro Rosso caused the damage.
But the Italian team denied the charge, moving Charlie Whiting to write a letter to all the teams asking them if a piece of their car was missing after the Sepang event.
"Until now he has received no answer," said Germany's Auto Motor und Sport.
Said Sauber team manager Beat Zehnder: "It could have been a drain cover."