Platinum

Yes, this thing really does work! We get great gas mileage.

I used it through 3 tankfulls of gas but didn't notice any imporvement in mileage, but will wait for summer driving to say for sure. Winter driving in Alaska is a lot of idling and warm up.

I read mixed reviews about this product. but wanted to give it a try nonetheless. This is a piece of garbage! Three tankfuls and not even .1 difference in gas mileage. In fact it continually caused static on my radio while in use. I'm going to try sending it back to see if they will stand by their satisfaction guarantee -- if not I guess you can say there was another sucker born during this minute.

Most reviews here are either manufacturer shills or ego maniacs who have never held this product in their own hands. That, plus because the Consumer magazine testing was intentionally or incompetently bogus, and Amazon super buyer friendly return policy is why I took chance and bought one. The 2 stars is because I cannot say it will not work for others and it did light up.I used this on 2 vehicles that are NOT diesel, NOT hybrid, and older than 5 years. A 2005 Chrysler T & C with the bigger of the two 6 cylinder options and a 1999 Jeep Cherokee with 4 wheel drive and 4.0 6 cylinder. Both have about 90,000 miles on them. Both get regular maintenance that I usually do myself if time permits. There is nothing I have not repaired or replaced on a vehicle over the years (not these specific ones though) and according to the US Army I am in the top 1% of the nation for being mechanically inclined, so I kinda know my way around cars and machines.The van made 4 trips of a 60 mile route of highway city mix. Exact same route each time and perfect weather with negligible wind if any. Without the device it got 22.9 mpg, with the device it got 21.4, 22.9, & 22.1 mpg.The jeep made 4 trips of 99 mile route again being identical environment and route and a highway city mix. Without the device it got 20.1 mpg, with the device it got 19.5, 20.1, & 19.8 mpg.So in final analysis the device did not show any increase and indicates an actual decrease (although small enough that further testing would be warranted to claim a decrease) after use of 180 miles on one vehicle and 297 miles on another vehicle.No major harm though. Amazon has refunded full amount and paid return shipping, so it didn't hurt to give it a try.If you are having ANY temptation to try it, go ahead, it really can't hurt, but I think most of the claims where people say it works are shills or people who are not very scientific and make subconscious assumptions, but that is far better than those who intentionally and consciously make negative claims for no more reason than spite and ego.Thank you and have a very happy day :-)

I was shocked when I used this and found that it actually improved my gas millage. I drive an 2000 Ford Explorer and tested it many times to conclude that it really did work in my vehicle. I tried it in a friends car, a 2006 Tuscon, and found very little improvement. I still rate it 4 stars because it works great in my SUV.

The bestselling, I, like it safe energy I, garante

I'm still evaluating the device. not sure yet if it is doing any good. it'll take another week or two because I'm not driving much right now

I purchased the Fuel Doctor for a trip from Las Vegas to Detroit and I found NO differance in mileage on my 1997 Pontiac Transport Minivan. I them tried it on my 1998 Buick Park Ave. I took a drive up round trip to Northern Michigan from Detroit and I found NO differance in mileage either. I think the Fuel Doctor needs a doctor. I requesting a full refund from Amanzon on this product because the claims that were made about an increase in fuel economy are FALSE!