Wiedeking was born in Ahlen, North Rhine-Westphalia. He grew up in Beckum, Germany, and attended RWTH in Aachen. After graduation in 1978, he remained at RWTH for graduate school, in order to attain a doctorate in engineering. He earned this degree in 1983.
His professional career began in 1983 as Director's Assistant in the Production and Materials Management area of Porsche AG in Stuttgart-Zuffenhausen.
A mechanical engineer by training, he joined Porsche in 1983, aged 31. After a stint at Wiesbaden based Glyco AG, a subsidiary of auto-parts maker Federal-Mogul, he returned to Porsche as head of production in 1991, taking over two years later as Chairman (CEO) when Porsche was close to bankruptcy. Due to Porsche's large shareholding in Volkswagen, Wiedeking also found himself on the supervisory board of that company. Some industry analysts believed that Porsche could not survive on its own, but Wiedeking, who says he made his first million by the age of 30 with real estate investments, took on the challenge.
Wiedeking, then 40 years old, who with his spectacles and moustache looked like "a clerk at a venetian blinds manufacturer", according to Der Spiegel magazine, soon imposed his gung-ho management style on the workforce. Within two years he managed a surprise turnaround by trimming the product line-up, modernizing the production system based on Toyota's lean manufacturing system and negotiating new work rules with the unions.
Wiedeking asserted in a 2006 interview that "every product must earn money. Otherwise you are simply pursuing a hobby, which is no task for an auto-business". By then he had dropped the unprofitable 928 and 968 models, overhauled the iconic 911 and developed two new models: the Boxster convertible and the Cayenne SUV.
Wiedeking played a leading role in Porsche's attempted takeover of Volkswagen, which was ultimately unsuccessful although windfall gains from financial instruments linked to VW shares helped Wiedeking become the best paid executive in Germany in 2008. The bid left the Porsche holding company with debts of €10 billion, whilst Wiedeking walked away with a severance package of €50million. After his departure from Porsche Wiedeking was charged with market manipulation for his role in the takeover bid.
Whilst at Porsche, Wiedeking appeared several times in the American automobile magazine Motor Trend's "Power List" (05/06/07/08/09). The article ranks the most influential people in the automotive world; in the 2005 article he was ranked as #6, in 2006 he was ranked #3, while in the 2007 article he was ranked as #4. Wiedeking dropped to #7 in 2008, but reached a personal high #2 in 2009.
Other accolades include2002: German Images Award
2003: CICERO Speaker Prize
2005: Honorary Doctorate from Handelshochschule Leipzig
2005: Peter Stihl Prize
Wiedeking is married and has two children: Isabel Wiedeking, born in 1983, and Wendelin Wiedeking Junior. He currently lives close to Stuttgart.