DETROIT (AP) — U.S. auto safety regulators are investigating speed sensor problems with Mercedes-Benz Sprinter full-size vans that could cause unwanted acceleration. The probe by the National Highway Traffic Safety Administration covers about 160,000 Sprinter 2500 and 3500 vans from the 2011 through 2018 model years. The agency says it has 44 complaints of rear wheel speed sensor problems that caused large fluctuations in speed and erratic transmission shifting. There were no reports of crashes or injuries. A message was left Friday seeking comment from Mercedes. The agency says it will investigate how often the problem happens and the safety consequences. The probe could lead to a recall.