Changes had to be made to use even 10% ethanol in gas that started in 2007, prior vehicle years do not have these change and it does cause damage to fuel pumps, regulators, and injectors. With evaporative emission controls, have three fuel lines between the tank and pressure regulator, fuel feed, fuel return, and just one on top of the tank to gather fumes. If any of these leak, could have poor fuel pressure, and really doesn't take much of a leak.
Switching the ignition on and off 3-4 consecutive times with out going into start will increase this pressure, have to examine all three lines. On the newer crap, putting the carbon filter at the back of the tank so only two lines too worry about, but that sucks up road water in a rain and put gas into your tank. Water is heavier than gas, fuel pump pick up is at the bottom of the tank, has to be if it were on top, would only get the top of the tank gas into the engine. Bean counters did this to save adding that third line but sure didn't decrease the price of vehicles, price goes up every year/
Shops around here love to replace fuel pumps, have to drop the tank, average price is around 1200 bucks. Most don't remove those three tubing fitting, cut them and patch with a piece of fuel line, that leaks very quickly.
Fuel pumps are not much larger than electric motors found in RC model cars, have carbon brushes close to an inch long, they get very short after 100k miles, some newer one are finally using brushless motors, like an induction motor, driven by and AC converter that can be made in China for a couple of bucks.
With OBD I cars removing just the negative terminal of the battery, all memory was lost including your radio presets, and the ECU learning was also lost. So the vehicle had to be relearned, on some would take a half an hour to set the idle speed, all this ended with OBDII where flash memory as we called it did not lose its data when the voltage was removed. And the same was with error codes. But some foreign vehicles are different, and Canada has different laws than our EPA.
First vehicle with fuel injection was a 1985 Honda SEI that used an external fuel pump that was very easy to replace, but because it was, even with 260K miles on it, never went bad.
Security is having a full tank of gas, but not if some idiot hits you, also that is when your in-tank fuel tank goes bad, no way to drain it, siphon it out, tanks were moved to the bottom of the rear seat, so do need an external fuel pump to get that fuel out. With three fuel lines coming out of the tank, have to guess which one works. Nasty job.
