* Reshuffle planned before start of IAA car show - sources
* Four of the board's seven members to be replaced - sources
* CEO Stadler to remain in office for now - sources (Adds details on possible successors, background)
MUNICH/HAMBURG, Aug 22 (Reuters) - The management of Volkswagen's luxury carmaker Audi will be reshuffled by the start of the IAA auto show in mid-September, several people familiar with the matter told Reuters, with four of the board's seven members to be replaced.
Audi, which is the biggest contributor of profits to Volkswagen (VW), is grappling with car recalls, prosecutor investigations and persistent criticism from unions and managers over the emissions scandal and its performance post-dieselgate.
Audi's Chief Executive Rupert Stadler will be spared in the reshuffle, flagged to Reuters by sources last month, unless new evidence emerges that would indicate he knew about diesel emission cheating at the carmaker.
"He still enjoys the confidence of the Porsche and Piech families," one of the people said on Tuesday, referring to the clan that controls Volkswagen. "Something significant would have to pop up to change that."
Audi and Volkswagen both declined to comment.
An Audi engineer was arrested in July, and his lawyers say he has made serious accusations against top managers.
But prosecutors say that Stadler and other Audi executives are not suspected of criminal action.
Audi's controlling panel is preparing to replace finance chief Axel Strotbek, production chief Hubert Waltl, human resources chief Thomas Sigi and sales chief Dietmar Voggenreiter, sources said last month.
Peter Koessler, the chief of Audi's plant in Gyor, Hungary, is seen as a likely candidate to replace Waltl. One person said VW manager Wendelin Goebel, a confidant of VW CEO Matthias Mueller and Audi CEO Stadler, may succeed Sigi.
German weekly Automobilwoche separately reported that VW commercial vehicles sales chief Bram Schot is to replace Voggenreiter and CFO Strotbek would be succeeded by Alexander Seitz, who among other has been in charge of procurement at VW do Brasil.
The sources told Reuters that no formal decision had been made yet. (Reporting by Jan Schwarz, Irene Preisinger, Ilona Wissenbach and Joern Poltz; Writing by Christoph Steitz; Editing by Georgina Prodhan)