last gentle reminder for those who like to change/cut lane without signalling or tailing close to front car, please think about the other road users' safety and YOURS!go bek n giv ur pops a brojob

the theory is possible as relies on thermal expansion of liquid when exposed to higher temperature. density per unit temperature

however there 3 thing you need to consider

1) petrol can turn to vapour easily at high temperature. As you guys already know, when liquid turn into gas, it volume expended. If your theory is following this principle, unless your car run on petrol vapour instead of liquid form. Feel free to pump

2) Petrol are stored in underground tanks and maintained at a constant temperature. Underground temp remain constant through out the year

3) This trick is well know that is why the pump have temp sensor to sense the petrol temperature and adjust its volume accordingly to its price. More often it is negligible but it vital for places that have great temperature swing such as in the desert which very hot at day and very cold at day. For oil company, their excuse is for customer to get maximun for what they pay for while in actual fact making sure u get what u pay for
false again, oil pump have filter which filter out impurities in tank. Modern car used fuel injection very much like a springer spaying mist of petrol into the combustion camber therefore it vital it is not jammed due to impurities blocking it fuel path . Again it does not matter your tank is 20% full or 50% full or 100%. There a float which indicate the level and the pump is always at the bottom level of the tank. No matter it still will suck in residue but it being filtered out
what fuel pump have to do with easing inhale of air? two separate system. If u want ease enter of air, change and wash your air filter regularly to free it from dust 

while It is a fact more weight = more fuel consumed. This again blown out of proportion. The fuel economic you see on a car publicly boasted by manufacturer is actual tested from a fuel tank and to a certain level. It also can be said the same as the more fat you are as the driver, the more fuel you going to consume
While it true, petrols have a lower density, generally an reduction one litter or 2 equate to reduction of weight 800g~ 1.2kg. For a car that weigh 500kg, your are just saving 0.20% in weight  . Does not make sense at all

pls, there are enginner in /k/ that know this stuff, dont believe in nonsense posted at Facebook news feed all the time

for engineers, ppl that believe in this kind of stuff are naive individuals who think they can outsmart a system which is already design to take this into consideration

i not sure are you try to be a gear head but in end get all the system function alll wrong?