I have seen this on my fuel rail since I bought the car. What exactly does this do? Is it necessary to keep on the vehicle?

 

i thought of that too. but i guess it does what it says especially on a returnless system helps fuel pressure be stable.. not sure what it really does

 

probably does the same thing that our "balance shaft" does haha

 

Do the return fuel systems eliminate this?

 

as far as i know all return systems do away with it simple because most come with their own fuel rail. the FPD (fuel pulsation dampner...I think thats the proper term for it) mounts on the fuel rail so with an aftermarket fuel rail there isnt a place for it to bolt onto.

 

btw the FPR (fuel pressure regulator) takes the job of this dinky thing (sorta)

 

So think its better to keep it in on a returnless sytem?

 

I dont see the harm in having it on a returnless system

 

I think its more for a returnless.. opening and closing of injectors I think creates pulsation due excess pressure backing to the pump so it kinda dampens it. On return system the excess fuel goes back like a one way traffic. i dont know just the way i see it

 

Makes sense....I guess Ill keep it in. thanks guys

 

Many fuel systems have this, both return and returnless. It's job is to balance the pressure drop in the fuel rail when the injectors open. When using a stock rail which holds enough fuel to supply 4 stock injectors you want a constant pressure and volume above the injectors. This helps maintain proper metering of fuel at all times. On a fuel system using a larger volume rail, high flow pump and larger regulator it's not as much of a concern as there is generally enough fuel on tap to avoid that problem.

 

Nice - Thanks Don