Technical Changing fuel filter
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Technical Changing fuel filter
You will not find it. If I read an earlier post correctly you have an 1.6. Change the pollen filter, oil filter (and oil) instead. 
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well.. you could find it.. it's part of the fuel pump on petrols (would advise against opening the pump.. unless you wish to replace it that is)
:yeahthat:
FIAT stopped fitting in-line fuel filters to their petrol cars some years ago. A cost saving measure no doubt. I guess you could introduce one by breaking into the fuel line somewhere near the tank. You would need to cobble together some kind of bracket to hold it though. I know early Puntos had a filter in-line, so that might be a place to start...
FIAT stopped fitting in-line fuel filters to their petrol cars some years ago. A cost saving measure no doubt. I guess you could introduce one by breaking into the fuel line somewhere near the tank. You would need to cobble together some kind of bracket to hold it though. I know early Puntos had a filter in-line, so that might be a place to start...
Most returnless fuel systems do not require a filter now and the one in the tank as part of the pump is sufficient enogh.
nope
Eh? Returnless? Surely all fuel systems must have a return line..?
Behold...
Returnless Fuel Systems
Have been adopted by several motor manufacturers and differ from the conventional by having a delivery pipe only to the fuel rail with no return flow back to the tank.
The returnless systems, both the mechanical and the electronic versions, were necessitated by emissions laws. The absence of heated petrol returning to the fuel tank reduces the amount of evaporative emissions, while the fuel lines are kept short, thus reducing build costs.
Mechanical Returnless Fuel Systems
The ‘returnless’ system differs from the norm by having the pressure regulator inside the fuel tank. When the fuel pump is activated, fuel flows into the system until the required pressure is obtained; at this point ‘excess’ fuel is bled past the pressure regulator and back into the tank.
The ‘flow and return’ system has a vacuum supply to the pressure regulator: this enables the fuel pressure to be increased whenever the manifold vacuum drops, providing fuel enrichment under acceleration.
The ‘returnless’ system has no mechanical compensation affecting the fuel pressure, which remains at a higher than usual 44 to 50 psi. By increasing the delivery pressure, the ECM (Electronic Control Module) can alter the injection pulse width to give the precise delivery, regardless of the engine load and without fuel pressure compensation.
Electronic Returnless Fuel Systems
This version has all the required components fitted within the one unit of the submersible fuel pump. It contains a small particle filter (in addition to the strainer), pump, electronic pressure regulator, fuel level sensor and a sound isolation system. The electronic pressure regulator allows the pressure to be increased under acceleration conditions, and the pump’s output can be adjusted to suit the engine's fuel demand. This prolongs the pump’s life as it is no longer providing a larger than required output delivery.
The Electronic Control Module (ECM) supplies the required pressure information, while the fuel pump’s output signal is supplied in the form of a digital squarewave. Altering the squarewave’s duty cycle affects the pump’s delivery output.
To compensate for the changing viscosity of the fuel with changing fuel temperature, a fuel rail temperature sensor is installed. A pulsation damper may also be fitted ahead of or inside the fuel rail.
Sourced from http://www.picoauto.com/automotive-library.html
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Ooops - I stand corrected. Learn something new every day!
