I just looked in my owner's manual at the instrument cluster photo & it doesn't show the economy gauge. Where I saw it on the instrument cluster of the 190e I was viewing was at the bottom of the left hand circle where the fuel gauge, temperature, & oil pressure gauge is located. I have had 300e's, 190e's, & a 240 diesel and all without the economy gauge like the one I saw listed. It just kind of grabbed by attention, because it was definitely a new one to me!