Hi all
Im looking at fitting a fuel pressure guage to my Windsor to see if i can locate an issue where it just will not make any power. The motor is very flat and wont oull on petrol at all. Its that bad the motor is making more power on the LPG.
I am suspecting the high pressure pump has cacked it due to it running dry when the low pressure pump died.(after market setup with surge tank fitted to 4wd).
I want to fit something like an autometer guage to the schroder valve permanently so I can monitor the fuel pressure as Im driving. The plan is to tuck the guage up underneath my bonnet scoop outside the car so I can see it from the drivers seat.

Here is the confusing bit. Do I need an isolater for the guage seeing as though it wont be in the cabin or is a braided line direct from the schroder valve to the guage safe?

Also what fuel pressures should I be getting out of my pump. I believe its about 45psi at idle and there is a figure at about 4000rpm but I cannot find it.

I have spent too much money on this vehicle to just go and through another pump in it without checking it is definately the pump. I am 95% sure it is but. If i put the guage on it but it will always be there when Im trying find problems like this in the future so I think its a good investment.
Any help is always appreciated.
Thanks Matt

If the gauge is outside the car then you don't need to run an isolator. You need two parts in order to hook it up to your valve & gauge, both made by Autometer. AU3280 & AU3228.

Base pressure I understand is 45psi, and should be close to this at 4000rpm as well.

Ok I put a guage on it today. Just wound up putting a speco one under the bonnet. I couldnt justify the extra $200 odd dollars it was going to cost me to have it on the bonnet to check if my pump was rooted.

I got 46 psi at idle with the vacuum disconnected. All good there. Turned it off an within 10 secs I had lost all fuel pressure at the rail. At run straight back down to 0.
Figured that cant be real good so I crimped off the regulator return to tank line to test if the pump was dropping pressure or the reg.
Started it up over 100 psi pressure when idling for a couple of seconds. Shut it down and once again within 10secs fuel pressure had dropped straight back to zero.
I figure the fuel is returning back past the high pressure pump instead of it keeping the rail under pressure. Is this a sign that my pump is stuffed?
Spoke to an EFI bloke today and reckons it is and it shouldnt drop fuel pressure when shut down. His thoughts are that the pump is had the roger and even though the pressure seems to be fine that if there is a problem for the pump to be bypassing to drop pressure that there is a good chance the pump is not flowing the volume the car needs creating the doughy performance.
Any ideas people. I would like an informative answer before I go and put the hand in the pocket for another couple of hundred bills for a new pump.

what pump are you using? Does it have a check valve in it?

The pump is meant to be a walbro , but I think i got stooged by one of the copy ones. Yeah I bought it off ebay awhile ago. No idea if it has a check valve in it or not.
I was under the impression that all EFI high pressure pumps have a check valve in them.