I can't provide any hard comparison data on my MPG, but it is not really in dispute that the amount of gas that the injectors spray to start the truck is much less than the amount that the injectors spray when keeping the truck at idle (idling for longer than anything super short). I do cringe when my Auto Stop/Start kicks in when I am at a stop I know is going to be less than something like 5 seconds (only happens occasionally), but for the most part it seems to only kill my engine when at a more appropriate location like a long red light that I am going to be sitting at for 60+ seconds or more. Does it add up to a visible change in MPG over an entire tank? Not for me, but possibly for someone who does a ton of congested driving in urban areas where there are a TON of traffic lights.
