VW board members demanded Piech go after learning of secret plot
* Piech drew ire of key board members by reneging on CEO pledge
* Ouster of powerful chairman ends public row but leaves void
* Winterkorn must tackle strategic problems highlighted by Piech
* Some worry CEO will be beholden to unions who saved his job
By Andreas Cremer and Georgina Prodhan
BERLIN/FRANKFURT, April 27 (Reuters) - Ferdinand Piech, who resigned as chairman of Volkswagen over the weekend, sowed the seeds of his own demise by reneging on a deal to support CEO Martin Winterkorn and secretly plotting to oust him instead, according to sources close to the VW board.
When news leaked out last week that Piech had been lobbying family members behind the scenes to install Matthias Mueller, the chief executive of Porsche, at the helm of VW, the company's powerful works council and its home state of Lower Saxony - a top shareholder - decided they had had enough.
They demanded a meeting of senior board members - the second emergency VW summit in a little over a week.
"It was one of the straws that broke the camel's back," a source close to one of the VW board's labour representatives, told Reuters, referring to a doomed attempt by Piech to convince fellow family members to dump Winterkorn and install Mueller. Continuación...