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Fuel rail dampener: needed or not?

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Old Apr 11, 2021 | 05:04 PM
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Default Fuel rail dampener: needed or not?

I bought an aluminum fuel rail for my 99 4.0. Three away my old rail because it was garbage to say the least. This aluminum rail doesn’t have a fuel dampener on it. Is it required for my 99 to run properly? Do they make aftermarket ones I could possibly attach if it’s needed?




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Old Apr 11, 2021 | 07:19 PM
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Dampener?
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Old Apr 11, 2021 | 07:26 PM
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Originally Posted by BlueRidgeMark
Dampener?
the top hat looking thing on the middle of the fuel rail. I was told it was a dampener and not regulator because regulator is in the fuel pump on a 99...?
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Old Apr 11, 2021 | 07:27 PM
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Originally Posted by joshastine
the top hat looking thing on the middle of the fuel rail. I was told it was a dampener and not regulator because regulator is in the fuel pump on a 99...?

Is this a regulator or dampener?


Last edited by joshastine; Apr 11, 2021 at 07:53 PM.
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Old Apr 11, 2021 | 09:00 PM
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It's a pressure dampener. No idea if it's truly needed though.


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Old Apr 12, 2021 | 02:43 AM
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I have always wondered about this myself.
My '00 has one on the fuel rail too.
Guys used to call it the flame thrower for when they leak.
Apparently there is a little O-Ring in there.
On top of that is a non serviceable part according to the parts catalog.
But guys have taken it off and replaced the O-Ring inside.
Personally I don't know if I would be comfortable doing that.
I have never seen an aftermarket one that has the dampener on it.
Doesn't mean they don't exist.
Pretty sure I asked the same question awhile back but never really got an answer.
Be curious what the outcome is here.
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Old Apr 12, 2021 | 02:35 PM
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You dont need it.
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Old Apr 12, 2021 | 08:41 PM
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I was just looking at the damper on mine...Judging by the name and shape of it I'm assuming it might be some type of diaphragm to smooth out the pulses from the pump itself as supply/demand change quickly...As to if or what you'd feel by not having it would be just a guess...
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Old Apr 12, 2021 | 09:53 PM
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It's not necessary. They were supposedly put there to dampen the sound of clicking from the injectors. At least that's what has been said about the 2nd gen Mazda Rx-7. It's common for people to remove them from those cars because (on the Rx7) it's made of plastic. Plastic, heat, fuel pressure, age... add those together and you get a massive fire. I've never seen any adverse reaction from removing the FPD, so it must be just for the noise. At least for that car, that is.
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