Thanks Phil,
Gauge arrived today and I've plugged it in between fuel rail and pump.
It shows 36psi when priming before starting engine and 30psi with engine started and stays at 30psi whatever the revs.
The only rising rate fpr's I can find using Google are in Australia.
Did you source yours in the UK?
Is it worth taking the original FPR off and trying to clean, do they stick like the tank return valve?
Appreciate the help so far.
Thanks Mark.
Ah, just taken fuel filter out and its completely full of sludge.
Just ordered a new one, so will see what pressure is like once fitted.