The fuel pressure on my car keeps droping. Its a nova, with intank pump and black top FPR. The pressure was set to 3 bar. I've got a fuel pressure gauge connected at the moment, when I start the car I get normal fuel pressure, then the fuel pressure will drop to 2 bar and the fuel pump will whine. I thought this was a dodgy fuel pump, I was using a Vectra one, but I've just bought and fitted a new motorsport fuel pump which can flow 2.9L a minute, and its still the same. The fuel pressure drops about a minute after starting the car, even at idle. Then if I turn it off and back on, when the pump primes I see pressure.
What could it be? I've not changed the fuel filter since I've had the car (3 years!) But have one here so will do that now.
Right, just changed the fuel filter, at idle it seemed to be better. So I adjusted the fuel pressure back down on the regulator (I had previously raised it as it was reading low even before the drop and pump squeals) I put it about 2psi higher to be safe.
Took it for a gentle drive, pressure remained good, so i hoofed it, and jeeze, its like a different car, its an animal!!! So I dont know if its gradually been getting more and more blocked since it was mapped, so I haven't noticed the difference, or what.
Cost me £100 for a fuel filter change, so thats a bit annoying, but its nice to be scared to look at the speedo whilst hooning it for fear of taking the eyes off the road again. Will never have to worry about the fuel pump again I guess.....
So if you've not changed your fuel filter for a while, go do it!