Figured it out, I think.

The pd on the s5 fuel rail was blown. When I tried to blow through the s4 rail there was a lot of resistance to the flow, however, on the s5 rail there was no resistance at all. I figured the lack of idle and the stalling could be caused by low fuel pressure. The loud hissing noise I heard was fuel flowing freely through the rails. Swapped the Pri. rail back to stock and she runs great. https://www.nopistons.com/forums/pub...IR#>/smile.png



Does anyone know anything about the reliability difference between the s4 and s5 rail? The s5 looks better to me but if the pd on the s5 fails just as often as on the s4 then there is no point in me getting an s5 rail for my car.



Thnx

Andy

I dont think that there is a real difference between the 2. I dunno though. Through my experiences so far, the S4 works great for me. I am pounding 60 psi all the time for a while and no probs yet. My car also has 95K on it. But new fuel setup soon so I wont have it much longer.

the s4 you can remove and replace the pd

s5 the pd is built into the unit basically, so to replace the pd you buy a whole new rail and PD.



a suggested move is to use a Marren Pulsation Dampener (injector.com) and make it work on the s5 rail do-able with the proper taps, but not done very often.



Ill be swapping toc ustom rails and FPR basically to avoid dealing with replacing a crappy design with the same stock crappy design.



the PD is like a bomb waiting to go off.



kevin.

I just deleted the pd on the black t2 tonight. Swapped the banjo fitting and bolt opposite from the opposite side of the pd from a different rail...

Are you having any problems with not having a PD? It seems to me like the PD helps keep the fuel pressure up and without it the fuel pressure will always be low. At least I think that was my problem.

I will let you know when its running. Bigturbo74 did it on his car...

i doubt the PD would lower your fuel pressure, in my random thoughts at least.



but hey, its all possible, hell my motor mount was ******* up my wastegate.



kevin.