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Installed the Fuel Shark Device. Would like to know the opinion of my TMC friends.

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Please tell me you are not serious. I have read many thoughtfull and wise posts from you in the Climate Change thread. Surely you must understand that you have bought a device with a blue LED and a 1000 mikro-Fahrad capacitor that can do absolutely nothing for your fuel consumption what so ever? In no possible way ever.

Excuse me Johan but we were talking about another thing, that is to say the function of filtering the 12V line. I said that because of this function maybe that now the lpg system of my car works. The fuel consumption is another matter. I also said that the calculations should be done exactly considering all the parts of the Fuel Shark to know exactly what it can do.
It's not only a capacitor with a blue LED IMO. There are also resistor (or having such function) components IMO.

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I'm starting to think he's Poeing us.

See: Poe's Law - RationalWiki

Don't understand what you mean. Please explain your thought.
 
Don't understand what you mean. Please explain your thought.

It's clearly explained in the link I included: Poe's Law - RationalWiki

Basically, it's nearly impossible to tell the difference between someone who takes an extreme position for real, and a parody of that extreme position.

You are taking an extreme position on the Fuel Shark which is a useless piece of junk that actually does nothing (and physics proves that, due to the tiny size of the capacitor.. the resistor is only a buffer for the LED and is not part of the capacitor circuit -- ALL LEDs need such a resistor to keep them from burning out). But you continue to hold this position, so perhaps you are just pranking us all with this extreme position you're taking with the Fuel Shark. The funny thing is, and this is Poe's law -- it's not possible to tell the difference if you're for real, or just pranking us.
 
@Hank

I am not taking an extreme position on the Fuel Shark. The only difference between you and me is that I am considering his usefulness while according to you it's not useful for sure. IMO at least some tests should be done to know if it's useful or not. I will test the Fuel Shark in the following days. To this concern I would like to say that while I was testing it the lpg system of my car (which was broken according to my lpg mechanic) worked fine!
Now I don't know it the Fuel Shark fixed my lpg system or not. I am only considering that the Fuel Shark could have fixed it (but maybe it didn't).

So my position is not extreme.

Don't agree there is no resistance useful for the RC filter. You are thinking in terms of constant values of the resistor and capacitor in the Fuel Shark which is only a simple way to represent an electrical circuit. In the reality any electrical circuit has distributed values of resistance, capacitance and also inductance values that become more and more evident when the frequency gets higher. But the distributed resistance, capacitance and inductance of any electrical circuit are always present also at low frequencies.
 
I think what you're missing, Raffy, is that people are referring to studies already done that show the FuelShark (and similar products) to not provide any value. You say tests need to be done, but tests have been done. For some reason you don't want to acknowledge that. And that's your right, but don't assume other people aren't relying on data.

Here's where I sit on this ... it's a $30 device, one I'd never buy. If Raffy wants to believe it's helping him (& clearly doesn't want to believe otherwise), let's remember it's the holidays and there is no reason not to believe in a little magic once in awhile. It doesn't hurt us a bit. :)
 
Sorry to disagree, but believing in magic does do all kinds of harm. First you buy a Fuel Shark and waste your money, then you want other people to do the same and waste their money, then (and here my argument goes right into the problems with religion and "magical thinking" in politics and I know that isn't allowed here so I will refrain).

Raffy, the Fuel Shark has been thoroughly debunked. You are welcome to try to test it yourself, but don't expect others to stop telling you that it's a scam. Because it is a scam.
 
Sorry to disagree, but believing in magic does do all kinds of harm. First you buy a Fuel Shark and waste your money, then you want other people to do the same and waste their money, then (and here my argument goes right into the problems with religion and "magical thinking" in politics and I know that isn't allowed here so I will refrain).

Raffy, the Fuel Shark has been thoroughly debunked. You are welcome to try to test it yourself, but don't expect others to stop telling you that it's a scam. Because it is a scam.

I think there are plenty of posts in this thread that others won't be led astray. I wasn't advocating to go forth and sing the praises of Fuel Shark. I was only pointing out that enough has been said in this thread to point out that it's a scam, Raffy is certain it is not -- and what harm is there in allowing him to continue believing? No one else is going to follow that path.
 
If so, please design a proper test plan so that your results are not biased at all. I'm sure that you will find that we are happy to help you review such a plan.

You are right. Yesterday I was doing the test under mixed conditions. But in this way same conditions of test when using the Fuel Shark and when not using it were not guaranteed. I will use same conditions of test in both cases.
 
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Thought that a scam couldn't be sold in the USA where consumers are very much protected by the law.

Quite the contrary my friend. Consumer protection and enforcement in the US is woefully inadequate compared to Europe.

Part of the reason that Fuel Shark still sells is that the company knows the average Joe actually has a limited understanding of how cars work and, at the same time, zero desire to get under the hood themselves. Take a look at your 12v outlet: it was originally designed to light cigarettes, it draws power from your battery, it does not contain a transmitter or receiver and is not a communication device with your car's electrical system.

Finally, it's also next to impossible for the average person to run a test that is truly scientific and without external variables. Raffy, when doing your test think about how weather and wind, elevation change, temperatures, and the drivers right foot can affect your km/L; and if your mechanic recently changed the spark plugs, that almost certainly made a difference to the car's performance.
 
No, it isn't. The older a car is, the less electronics there is, and the less components are suceptable to noise.

Note that *if* there was an issue with excessive noise on the 12V line, it wouldn't affect the fuel economy. It would manifest in things like random reboots, flickering monitors, warning lights ligthing up and going away, noise on the sound system, etc. And the capacitor is almost certainly too small to help with such issues.

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View attachment 65036

And as I explained earlier, there is no RC filter. There's just a C.

It that really the complete system ??? Not even a good scam then.

And a 1000 uF capacitor parallel to your Lead-Acid ACCU ??? That ACCU effectively acting as a VERY, VERY much larger capacitance dampening voltage fluctuations.
For fast high-frequency spikes a capacitor might do something to surpress. A 1 nF would do more for spikes than this.

A 1000 uF Elco can do nothing functional here in this 'system' other then making your LED glow a few moments after disconnecting this 'system' from the car.

Return this ASAP and ask for a refund.
 
It that really the complete system ??? Not even a good scam then.

And a 1000 uF capacitor parallel to your Lead-Acid ACCU ??? That ACCU effectively acting as a VERY, VERY much larger capacitance dampening voltage fluctuations.
For fast high-frequency spikes a capacitor might do something to surpress. A 1 nF would do more for spikes than this.

A 1000 uF Elco can do nothing functional here in this 'system' other then making your LED glow a few moments after disconnecting this 'system' from the car.

Return this ASAP and ask for a refund.

Some systems would include a cap to level the 12V locally. While the battery does sort of do the same function, there is a long bit of inductive wiring to get to that outlet. So that cap would have some effect in keeping the blue a steady state of blue-ness. But if I were designing the shark I would have cost-reduced that right out and let the light flicker a bit. Just a resister and LED is the optimized scam circuit.

Wait, why are we assuming they are in parallel? It looks like the cap could be in series, which maybe would turn the LED off and on once in a while based on 12V system fluctuations. Still snakeoil, but flashy snakeoil.
 
For $39 I would prefer a flashy one over a vanilla bland model. Give me more LEDs.

There was a time when there was a battle on LED lights on stereo systems from Japanese companies like Sanyo and Panasonic. More the merrier.
 
For the avoidance of doubt, I've drawn the trivial circuit that I can glean from the tear down picture elsewhere in this thread.

FuelShark.png


The current flowing through the resistor and LED is ~2.5mA (12 / 4700). A 1000µF capacitor can store 72mJ of energy at 12V, or 20µWh (0.5 * C * V[SUP]2[/SUP]). A typical automotive battery is rated at 60 amp-hours, which at 12V is 720 watt-hours of energy (12 * 60). The ratio of these energy storage capacities is 27.8E-9. The filtering effect of adding a 1000uF capacitor in parallel to the 12V battery is quite negligible.

There is no possible way this circuit can do anything useful across a 12V automotive battery, other than emit a soothing blue light.