If they did the auto manufacturers would already be using them.
A fuel return line should flow freely back to the tank. There may be a check valve on the fuel return line that prevents backflow from the tank to the regulator.
All you have to do is crawl under the vehicle and look for the line running from the fuel tank to the engine. But you are wasting your time and money. Fuel line magnets is another one in a long line of fuel mileage scams. They do not work. The EPA has tested these things and they provide no benefit whatsoever except to the person selling them. He will line his pockets with your hard earned money and you will be poorer and wiser. Ask yourself this question. Why do car manufacturers spend hundreds of millions of dollars in fuel efficiency R&D if a piece of magnet clamped onto the fuel line can already provide up to 35% savings in fuel consumption? I will post an excellent article on this useless device. Read it and save yourself some money. Also consider this: fuel economy is a BIG selling point. If a magnet clamped to your fuel line really could give you a 35% boost in fuel economy, there would be a person on the assembly line in Detroit clamping magnets to fuel lines as the cars were being built.
Magnets is made of iron. Magnets are attracted to anything made out of iron.
Should be under the vehicle - follow the fuel line from the tank
Magnets are attracted to anything with iron in it. Rust is Iron Oxide, so yes!
Yes. if the magnet is powerful enough, the magnets can attract through virtually anything.
due to magnetic line of force. opposite pole present in magnets.
pressure test line comming from fuel tank,one of two ways,1.disconect line from fuel filter on side where fuel line connects from fuel tank,if pressure 26psi to 35psi reconnect line to filter and check your line on other side of filter if pressure holds your fuel pump and fuel filter are ok,the other way is to disconnect inlet line from tank to fuel regulator and check your fuel pressure,the only thing with this method is if your fuel filter is clogging or clogged you will not get an accurate fuel psi.you can also check your fuel regulator,you fuses,or your relays to anything that has to do with your,depending on what type of car you have
anything that can become polarized such as metals
The short answer is: no, magnets do not increase miles per gallon. Some gasoline blends or other fuels have molecules with some small degree of polarity, but the use of magnets has no meaningful effect on any flowing fuel in a line, stored in a vessel, or igniting in a cylinder. Magnetic fields cannot make a fuel chemically, hydrodynamically, or thermodynamically any more efficient in any real world use. The only possible place where magnets could possibly improve fuel economy would be as a ferrous-metal trapping filter. (However, if you have ferrous objects in your fuel supply, you already have problems far beyond any corrective filtration.)
fuel vapor line is common in the car fuel line
Yes. Loosen the gas cap, and look for a Schroeder valve on the fuel rail in order to relieve fuel pressure. When you disconnect the fuel line be prepared for a spray of fuel. Wrap the connection with a rag and then disconnect the fuel line. The rag will stop the spray of fuel from hitting you in the face.