INTERNATIONAL PROSTAR (2013)

Investigation Summary

20151204 15V776000 Accelerator Pedal Fails to Return The Office of Defects Investigations (ODI) opened Preliminary Evaluation (PE15-013) on 2012-2013 model year (MY) Navistar Prostar vehicles for throttle pedals failing to return to the idle position after being depressed.EWR field reports supplied by Navistar describe the non-returning throttle pedals as preventing the engine brake from activating and elevated engine speed making it difficult to stop the vehicle.ODI contacted complainants who alleged the accelerator pedal didn?t return to the idle position.Some drivers indicated they were annoyed, while others stated that at idle they were able to keep the vehicle stopped but need to apply more pressure to the brake pedal.Some consumers indicated that the engine speed was so high with a manual transmission that the engine-brake would not work, while other stated they were able to pull the accelerator pedal back from underneath with their foot and bring the engine speed back to normal.In Navistar?s response to an ODI information request letter, they made ODI aware of 24 consumer complaints concerning non-returning pedals, mostly on manual transmission vehicles.There were no crashes, property damage, injuries or fatalities reported.Navistar identified 1,233 warranty clams related to all accelerator pedal issues, with 70.3% of these claims were on manual transmission vehicles.Navistar informed ODI that they became aware of an unauthorized part change to the throttle control unit assembly (manufactured by Williams Controls) from April 2012 to March 2013.This unauthorized change was corrected and all vehicles were being retrofitted with the new/original designed part.The design of the subject vehicle throttle pedal is a solid-state rotary position sensor device, which transfers voltage based on shaft rotation in either direction from a reference angle.Shaft rotation is obtained by the driver stepping on the accelerator pedal or allowing the pedal to return back to close