One problem related to engine rattling and whining sounds has been reported for the 2012 Ford Explorer. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2012 Ford Explorer based on all problems reported for the 2012 Explorer.
Turbo gone bad - car began making loud rattle noise when started. Noise would subside some after a few minutes. Car has been very slow to accelerate, whenever it's being driven, over the last few months. Have to really press down all the way on the gas in order to keep it going. The mpg have been steadily declining as well over the last few months. Dealer told me it's a "turbo problem". Was told that 180 other 2012 Explorers are also affected, parts on back-order for six weeks. Can't drive car. Repair cost approximately $3500. Ford offering no relief at this point.