Fuel Pressure Regulator drops to 0

[Disturbed32]

Hey all, just finished installing a set of second hand 270cc injectors from another RB20 I have, I installed a walbro 460 and a Turbosmart FPR1200 (Fuel pressure Regulator) and I’ve noticed on the gauge as soon as I turn the car off the fuel pressure drops to 0.

my car is an R32 gtst rb20det.

I’ve been reading through some forums and getting mixed replies, is this normal? People are saying not to worry, and that it’s just returning to the tank, but I thought I’d ask here anyway.

Fuel pressure is set correctly, it’s set in the right spot and there’s no fuel leaks, it primes and holds pressure and starts fine and holds pressure fine when running, but when engine is off it goes to 0.

any thoughts? Should I not worry? 

[r32-25t]

It’s normal 

[Ben C34]

Dropping back to zero quickly isn’t normal. 

[Murray_Calavera]

Sounds like your fuel pump doesn't have an internal check valve (or it's failed). 

In any case, if it starts fine - happy days! The the only downside of not having the check valve in your fuel system is it can be hard to start while your pump builds the initial pressure for the car to start. 

TLDR. She'll be right mate. Don't worry about it. 

[r32-25t]

38 minutes ago, Ben C34 said:

Dropping back to zero quickly isn’t normal. 

Is with a turbo smart fuel pressure reg 

[Ben C34]

2 hours ago, r32-25t said:

Is with a turbo smart fuel pressure reg 

I've got a turbo smart reg

[BK]

We've found the Walbro internal check valves are garbage on their pumps, as in may as well not be there. A speedflow check valve absolutely will not do that and sometimes hold around 30 psi for days like on my blue 32. It has 2 speedflow check valves (one on each pump from surge tank) and an SX fpr with 3 AEM external pumps.

Our white 32 has a Walbro 285 with internal check valve 525lph pump and Turbosmart FPR1200 and it drops slowly to 0 after shutoff with definitely no leaks.