Fuel Economy Booster: Review of Fuel Doctor Device

[russ_watters]

Saw this for sale at Best Buy: http://reviews.bestbuy.com/3545/9754101/fuel-doctor-fuel-efficiency-booster-gray-reviews/reviews.htm

The claim is that via power conditioning, the device improves the accuracy of your car's sensors and other electronic devices, thereby improving the car's efficiency.

I have my doubts, but the power conditioning claim was on its own intriguing: my car has an issue whereby noise is introduced into cigarette-lighter powered audio devices such as an mp3 player or my phone. The pitch of the noise rises and falls with the car's rpm and disappears if I unplug the power and run on the device's battery. One of the reviews is about this issue:

I will be specific. I have a 2010 Evo X. I installed an aftermarket headunit, and had some noise in the speakers from it. I also got bad gas milage (tuned w/ every bolt on so this made sense) and am in the search for every HP I can get.
Needless to say I decided to try this out. There is another version of this made by a japanese company that's been arround for a while. I believe the company is JUN, and just like this device, people say it works. Well I knew the only way I would find out would be to try it myself.
I had it for about 2 weeks. With the noise playing through my speakers I plugged this little device in, and noticed zero difference in sound. My MPG did not change a single bit, and i felt no power increase at all.

I don't see any technical magazine reviews for it, though. Opinions?

 

[Drakkith]

I have serious doubts about this product. Electronic devices have their own circuits and such to step the power up or down to the exact amount needed, and usually arent too affected by small fluctuations in power. If you have major fluctuations that are affecting your electronics, then it is likely you have a problem with the power supply and distribution in your car that will not be fixed by a "conditioner".

I'm willing to bet your noise you are hearing is simply interference due to your cigerette lighter socket being not shielded properly or something.

 

[Ivan Seeking]

While it may or may not be true that automotive electronic systems are generally insufficiently immune to noise, it could be true for some cars, and it is true that transients and noise can offset sensor values. The problem I see here is that isolation normally occurs either on a sensor by sensor basis, or by addressing the noise at the source - usually both. It is hard to see how even a very low ESR capacitor or active cancellation system would be effective without appropriate placement. There is no reason to think the utility outlet would be a good or effective location for noise suppression; say for something like a fuel injection sensor deep in the engine that is skewed by noise from the ignition system. You would need to get between the two systems in question.

One could poke around the engine with a scope to see what's there.

 

[Ivan Seeking]

Thinking about this... I can imagine that heater fan noise, and noise from items like a custom radio/CD player - esp high-watt systems - might be suppressed at the fuse block for the dash. But I would still be surprised if critical sensors weren't already isolated from system noise. Then again, I see a lot of things that surprise me.

 

[nismaratwork]

http://news.consumerreports.org/car...e-consumer-reports-fuel-economy-mpg-test.html

The EPA and consumer reports would seem to call this bogus, although the EPA has not singled out this specific iteration of the same product.

http://www.epa.gov/otaq/consumer/reports.htm