Have you heard of water cars that don't use fuel?

Have you heard about the water car kit? They say it is possible to drive your car using water instead of gasoline? Is this true? What information do you have about it?

In recent years I've heard many things about supposedly being able to run a car on water. So far as I'm aware, none of them have so far proven to be real, and there aren't conversion kits commercially available to make your car run on water (a vehicle engine cannot be powered by only water as they are). I would think if it was true, and really worked, then everyone would be converting their cars and you'd know all about it.

It's a myth, and impossible* - like perpetual motion. The theory usually goes:
1) Electrolyze water to get hydrogen and oxygen
2) Use the hydrogen to power the engine, generating power for the electrolysis
3) ...
4) Profit!

However, even at 100% efficiency, electrolyzing water takes as much energy as you get from burning the resulting hydrogen. In reality, nothing even approaches 100% efficiency, so it's even less practical. Basically, it's an attempt to get energy for nothing.

* Yes, yes, if you could build a fusion engine into a car, you could use water to power it. But that's _seriously_ in the realm of science fiction for the forseeable future.

Yes it is right, thousands of people not only America but around the world using this amazing technology. The people says it does not work or its a scam, I just say to people who say this is a scam then why thousands of people are using this and getting results.

People who don't know how to do it properly will say its a scam. To get more information about this particular technology just visit http://runyourcaronwater1.blogspot.com I have created this site to help people to convert their car to run on water using this simple technology.

What mohra is talking about is not a water powered car but a car that uses water with hydrogen electrolysis to improve gas mileage in addition to gasoline. For more info, see here: http://scienceblogs.com/goodmath/2008/05/bad_gas_math.php

It's important to note that _nobody_ has performed a proper controlled test on this. Until I see one, I'm highly skeptical of any company trying to sell overpriced devices for improving gas mileage. Every other one is bunk; this one probably is too.