South Africa's competition authorities are investigating price fixing and collusive tendering in the automotive industry, with top Japanese component suppliers Panasonic and Mitsubishi Electric Corp among those being probed.

Information received by the Competition Commission suggested collusion among automotive component manufacturers when bidding for tenders to supply parts, such as electric power steering and spark plugs, to car makers.

"The commission will prioritise the investigation of cases that involve automotive components that are in vehicles assembled in and supplied to the South Africa market," commissioner Tembinkosi Bonakele said in a statement.

Competition authorities said information in their possession pointed to 82 component manufacturers colluding over prices for 121 different automotive parts in the 14 years since 2000.

Officials have clamped down hard on collusive activity, fining construction companies millions of dollars recently in a bid to break anti-competitive behaviour in Africa's second largest economy.