With the vacuum line [B]disconnected.[/B]
[B]Drive [/B]the car on boost whatever base pressure you set (set it high to be safe) does the pressure stay constant?
Or does the pressure drop?

Pressure will not rise with the line disconnected.

If the pressure drops with high injector duty cycle you have a pump volume issue.

I did some more testing.

Set the SARD on 50psi base pressure and went for a drive with the vac line off. No fluctuations of fuel pressure on boost. Confirmed the fuel pump is 100% operational

Installed a Gen 2 Legacy TT OEM FPR with a base pressure of 48psi that I got off Teejay. Set boost for 14psi. Hit 62psi fuel pressure at 14psi of boost. That is correct operation for a 1:1 rising rate FPR. Although the TT FPR base pressure is quite high, its still operating correctly. Also, as soon as engine is turned off, fuel pressure is maintained in the lines

Confirmed the SARD is faulty. Sending it back for replacement.

Well I got my new replacement SARD FPR.

Still got problems. Going up to 16psi of boost, fuel pressure only rises by 8psi.

Its better than before but still not good enough. Im sick of this already. Im just gonna try to get a refund and try a different brand altogether. Or just use a OEM FPR from a GD which as a 43psi base pressure.

OEM reg and a squeeze up in the vice.;) Set whatever pressure you want.

^^ WHS - I've used the squeeze and test method on my 13b turbo's a few times in the past......It's how the manufacturer sets all the reg's the same at the point of manufacture.

I thought Sard was a 'good' brand? Are you sure they're not chinese sard rip-offs?

There was an issue with Chinese rip-off Malpassi rising rate regs years ago.

Mine is definitely genuine SARD.

fuel pump.

Its not a fuel pump issue Stace. Its a 2 year old Walbro 342.
It holds 50psi base fuel pressure with the vac line off on full boost.
And it operates properly when a OEM FPR is used. The TT OEM FPR has a high base fuel pressure but rises the fuel pressure properly in accordance with boost.

problems with 3 different fprs, including the stock one.
my money is on the pump still :)

Borrow a pump to try?

15 minute job.... V's banging head against wall?