Do not believe whatever you read. The stuffs from Wiki are flawed at times.
Nobody exactly knew what happened to Senna's car prior to the crash. It just seems his car veered off track in the Tamburello bend and smacks so hard into the barrier.
Just by the way, there was a court case involving Adrian Newey and Patrick Head whereby they were accused of causing death. Few years back, the two were cleared of manslaughter charges. Apparently, the steering column broke and there was no steering input leading to Senna crashing heavily coz unable to steer. However, Williams of Newey and Head said that the steering column snapped due to the crash and said that track debris caused Senna to lose traction.
So, Senna's death remain a mystery. However, one thing for sure. He was hit by his suspension rod on the head, thru the visor. That headblow probably killed him. Also, his in-car blackbox was mysteriously removed and was unreadable after being removed. Unconfirmed reports says that it was the work of some engineers that was trying to coverup something.
Also, apparently some onboard video shots were also missing, particularly 1 or 2 seconds before his impact. That would have showed what happened and what he did to the steering before he crashed.
Whatever that is, its 12 years since he died and his death is a great loss the the racing community. No doubt he's special from the rest of the great drivers. However, his full potential was never realised and he'll go down as one of the best drivers ever to race in a F1 car.