My 2016 ecodiesel has 30,000 miles on it. I recently started having the electronic throttle control message and loss of power/stalling above 3000 rpm. It has been at the dealer for 10 days and they claim they had some specialist from corporate look at it and the fuel was tested and it contained DEF. I replenish my own DEF and I know I have never added it to the fuel tank. How would you even get the flimsy spout past the 2 flaps in the fuel filler? Dealer says I need a new engine and they already have $2,000 into the diagnosis and parts plus a new engine at $12k. I’ve been going to this dealer for 30 years and have no trust issues. Looking for advice, thanks!