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22

If you think about what the car is doing in both cases you'll see why you burn more fuel when accelerating. General theory F = mA (Force is equal to mass times acceleration), and in this case the force is applied by the engine. The more force, the more fuel is burned. Acceleration In stop and go traffic, you are making frequent stops, and accelerating ...


16

Every time you brake, the energy is wasted. Brakes convert mechanical energy of a moving car into heat via friction (they heat up). This is where the energy is ultimately "lost". Then, when the traffic moves forward a bit, you of course need to accelerate - and this is where you actually use gas from your tank to put this energy into getting your car to move....


11

Regulations limit the amount of unburnt hydrocarbons that can be released into the atmosphere, therefore fuel tanks on cars now have to be sealed to stop these emissions. The noise you hear is air rushing into the fuel tank, due to the low pressure caused by the use of fuel.


8

Your engine is always burning gas when the car is running. When you're stationary, you are burning gas to keep your engine running, without actually moving the car, so you're actual miles per gallon (MPG) at that moment is 0. When you begin to accelerate, you are using more gas than when the car was idling, but then you have to press the brakes, ...


6

Yes, running low on fuel can damage your fuel pump, but as IHaveNoIdeaWhatImDoing mentioned in the comments below, modern fuel tanks are sophisticated enough to prevent fuel pump starvation until the tank is almost complete empty. Either way, damage to the pump can occur because fuel acts as a coolant for the electric motor. When there is no more fuel the ...


5

There is Brake-Specific Fuel Consumption Which is a measure of how much fuel is consumed per unit energy. Another way to look at it is the rate of fuel flow needed per unit power developed by the engine. This information is not something accessible through OBD-II. But it's not very useful in this case Note that MPG remains relevant because it is a ...


5

That pipe probably goes to the tank too, it is just there to let air out of the tank while adding fuel down the main pipe. I believe that your additive will be in the fuel.


5

For the sake of putting answers on questions... The WD-40 Website lists 100's of uses for the product and one of them is actually: Removes adhesive tape without damaging factory paint. So, it sounds like that advice is good. I second DucatiKiller's comment about Goo Gone or similar "citrus" cleaners. I've had good luck with them on automotive paint. ...


5

I worked at a shop that repaired fuel tanks and this is what we did. No cutting corners, each step depends on the last. The shop had a fancy caustic soda tub and some of the techs would call that an acid bath, but we used this on very few tanks. Mostly small, well constructed, steel motorcycle tanks. This is what we did for the other tanks that were not ...


5

Hydrogen is an ideal gas to be used for combustion, as there are no harmful emissions byproducts if the combustion (combination of hydrogen and oxygen) is at the proper ratio. You just make pure water, which is fine. There are several vehicles and several vehicle companies which have explored the concept of pure hydrogen as a combustible fuel. The ...


5

You could take the screw out of the center of the knob. Remove it, then put it on only to shut off or turn on the fuel.


5

It sounds like you have a motorcycle with a carburetor with gravity fed fuel line. (i.e. Without a fuel pump of any sort). In those conditions I can see that there is a higher fuel pressure at the inlet to the carburetor when the fuel tank is full. It's possible that when the tank is low the pressure is barely enough to meet fuel demand. With that said, ...


5

Long story short, yes it is an option. Whether or not it's a good one is another discussion. Good News: finding a replacement gas tank and having a competent mechanic replace it shouldn't cost anywhere near $2000. Especially if you find the gas tank yourself. I'd be curious to know how your mechanic intends to fix your gas tank and add up his services to a ...


4

In the case of topping off, it would make absolutely no difference other than costing you more at the pump. Octane is a rating which would indicate how hard it is for the fuel to burn. The higher the octane rating, the harder to burn. If anything, leaving gasoline for longer periods of time is going to make it harder to burn, thus effectively raising the ...


4

If you have no money, the simplest way to get it fixed is to use a stainless metal screw (or galvanized if you cannot find stainless). Simply screw it into where the hole is at. When you insert the screw, the metal of the tank will form around the screw. This is an "old timers trick". Back in the day when a tank would get some water in it (because of bad gas)...


4

There are a few ways to resolve this dent issue. Method 1 glue these plastic ding tabs to the gas tank. You can find them by googling "plastic ding tab" You will use a hot glue gun and hot glue them to your gas tank. Use a dent puller slide hammer. The tip should screw into the plastic ding pullers. Pull the weight of the slide hammer to the bottom ...


4

With the filler neck is a fuel breather pipe which allows the tank to vent air otherwise trapped when the fuel level is topped up. It may be that a breather pipe has become blocked. This can mean that fuel in the tank is effectively being held in a slight vacuum making the fuel pumps job harder and starving the engine. One good way to check this is, if ...


4

My theory is you have a stuck float in your carburetor. This is causing the fuel bowl not to fill completely. When you go around the corner, the main jets are without fuel (sucking air) and this kills engine power. Getting the carb rebuilt (or at least looked at) will probably solve the issue. You may also try using a plastic handled screwdriver and using ...


4

The gas gauge is just an indicator and each vehicle is going to be different. I know the older Datsun Z cars had two gas gauges, one was the main one which showed the volume of gas down to 1/4 tank, while the secondary one showed from 1/4 down to empty. The secondary gas gauge was very accurate to give the driver a true indication of how much fuel was in the ...


4

It is because the fuel lubricates and cools the pump. If you leave the tank run dry, the fuel pump will turn dry, which will overheat it and may cause the electric motor to fail or otherwise to reduce its service life. The same principle applies to the water pump when it is electrically driven, like in the Toyota Prius. When burping those kind of systems, ...


3

possible vent hose issue As you are filling your tank the displaced gasses in the tank need to go somewhere. If you have a pinched vent hose it could fill slower or be difficult to fill. Check the neck to the tank as well as the ventilation system to ensure there are no obstructions preventing the movement of gasses or liquids entering or exiting the ...


3

Are these instructions accurate? These instructions sound accurate to me. Would Vaseline-brand 100% pure petroleum jelly (the one used for baby diaper rash) be a suitable "petroleum-based lube" or is a car-specific product needed? Absolutely. And if I use a 100% cotton fabric to clean the top of the gas tank, does this suffice to minimize the ...


3

The level sensor works with essentially sliding contacts. These contacts wear out over time and crud, dirt and corrosion can build up on them. Did i mention that the sensor is submerged in gasoline. Some cars have known problems with level sensors but i'm not aware of BMW specifically having a problem. If you don't want to spend any money this problem can ...


3

All modern motorcycles with steel gas tanks have an internal coating that protects them against oxidation (rust). There are many brands of sealer available if the stock sealant has been compromised, typically due to heat or old fuel sitting in the tank for an extended period of time. This google search for 'motorcycle gas tank sealer' yielded these results....


3

OK, so the problem was that, due to a faulty fuel gauge sender, I over filled the tank. And since the seal around the top of the 'hatch' had partially disintegrated, well this happened: When parked on an angle, fuel was just flowing from the top of the tank :/


3

You can use hydrogen gas, yes. The main problem is that it is not easy to make. Most hydrogen (about 95% of all hydrogen used today) is produced by partial oxidation of methane and coal gasification, with some from biomass gasification. A tiny amount is produced by electrolysis of water (but it uses a lot of power to do so) So, yes, you can use anything ...


3

Hydrogen has been used as a fuel in various experiments. The largest-scale experiment I'm aware of is the BMW Hydrogen 7, a 7-series V12 produced from 2005-2007. About 100 were built. This engine could be switched from gasoline to hydrogen. The difference in fuel consumption is largely due to the different energy density with gasoline (petrol) yielding ...


3

Another way to view this is to visualise throttle opening. When you're cruising, the pedal is held down to some position more than idle, but less than maximum When you're taking off and accelerating, the pedal is pressed down further, which opens the butterfly valve allowing more fuel/air mixture into the engine. Hence more fuel is used to accelerate ...


3

The most important aspect of the answer to this question is found in Newton's first law of motion: An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. This is the same reason that space shuttle use something like 90% of their fuel on take-off. ...


2

I have seen two things cause this problem. The first is an obstruction in the fuel filler neck. This could be caused by damage or a foreign object logged in the neck. The second is if a EVAP vent solenoid is stuck closed. The evaporative emissions system collects access vapors from the fuel tank in a charcoal canister. To dispose of the collected vapors ...



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