hey everyone. i recently noticed a fuel leak above the turbo, and upon doing some searching around here, many have said it is either the pulsation damper or injectors...well i got around to taking apart the throttle body and removed the UIM and now i have a clear view of the injectors and fuel rails...

now here is the strange part. the previous owner did something to the primary rail and it looks like he put an AN fitting on it which deleted the pulsation damper...i'm not sure if it is causing the leaks or not, but i tried searching and have not come up with an answer to why this was done or if it has any drawbacks or benefits...anyone have any info on this setup? i'm just trying to fix the leak and get my car running again... Thanks

PS: i have an S5 TII

 

wow ... wow ...

 

thank you SO much for your words of wisdom and insight....

anyways i also just realized the S5 PD is welded onto the fuel rail...so im assuming that is an S4 fuel rail...im beginning to realize the previous owner is an idiot

 

If the s5 pd is welded on he could have chopped it off and tapped the rail for the AN fitting.

 

wow ... wow ...

 

You do know the AN fittings are on the primary rail.... right?

And that the pulsation damper is located on the secondairy rail... right?

And that the damper is clearly still on there... Right?




Ow and you know that you can run the fuelpump with the jump connector, as stated in the service manual to check for leaks... Right?

Wow... Wow...

 

FSM tells me the PD is located on the primary rail and the pressure regulator is on the secondary

and yes i do know you can run the jumper to prime the system to check for leaks...I was only asking about the setup in the picture.

 

Ow wait, i guess the alcohol was still talking haha.. its the fpr, not the fpd on the rail

Damn those holidays!

 

that's exactly why I wow in the first place.

wow ... wow ... (again)

 

Is there a vacuum line running up to that dashpot on the secondary rail? J-spec engines have backwards fuel flow which would make the FSM wrong.


You should jumper the fuel pump test connector with the rails exposed like that and turn the key on to help you locate whatever is leaking.

 

Seriously??? You're onto something though, you didn't explain it, but I think this is what you were getting at: the easy way to tell if the unit on the end of the secondary rail is a pulsation dampener or an FPR is whether it has a vac nipple on it. Vacuum nipple: FPR. No vacuum nipple: pulsation dampener. Though it already looks more like an FPR to me.

^^^ this

 

maybe one of the AN lines is loose? mine got loose once and leaked fuel near the injectors. derp.

 

It looks like deleating the fuel pressure dampener isn't a big deal.
http://www.rotaryresurrection.com/2n..._dampener.html

Idk if this helps...

-Matt

 

i replaced my dampner when i did my motor. mazda put it there for a reason (besides to set the car on fire)

pressurise you fuel system and look for the leak, pop the plastic cover off the dampner and see if the screw fell out or its leaky

 

New pulsation dampeners are very expensive from Mazda. I would recommend going the banjo bolt route personally. Got it done on my car, as well as a few friends do as well.

 

Yeah and Mazda put the Subzero Starting Valve on for a reason so it shouldnt be removed. Mazda puts a lot of things on cars for stupid reasons, it wouldnt cause any harm to delete another one or those stupid things. (PD)

Experience: Mazda Technician, licensed Automotive Service Technician.

 

So if these can be removed, whats the best way to block them off?

Also can you yank the stock FPRs and go to an aftermarket setup?

 

Banjo bolt.

You can, but the question is.. Do you need to?

 

Banjo bolt, it is in the FAQ i think..

Yes, either use S4 rails and screw in a fitting, or cut off the fpr and weld in a bung on the S5.
I cut my S5 rail and welded in a bung with hose connector. But getting a proper sealing weld is not always easy. Remember that there will be FUEL leaking, so if you do not have the proper welding skills, buy S4 rails!

 

so the PD is safe to be deleted. sounds good, i guess i will just leave it as it is...

on a similar note, has anyone ever heard of or used RisingRPM's FC fuel rails? it comes in a set with all new hardware, and both primary and secondary rails, but there is no PD or FPR...since it doesnt have an FPR would you need to get some aftermarket FPR to replace the stock one?