Car is a '74 2.0 with original D Jet injection.
Having a bunch of weird problems, and learning as we go about this FI. Decided to go back to the basics and put a fuel pressure gauge on it. Gauge is just before the first fuel rail.
When you turn the key on, the fuel pump activates and jumps to 28 PSI, but the minute the activation stops, it drops to 18 PSI. Fired up the car and it holds at 28.
Clamped off behind the fuel pressure regulator, and it still went from 28 to 18.
One spark plug is consistently wet-#4. All injectors were rebuilt. Has 130 lbs of compression and spark. New Pertronix, cap rotor and wires. All other cylinders look normal.
Is the fuel pressure drop normal? Or is it indicative of a leaking fuel pump check valve or leaky injector?
Thanks-