I got my 1970 914 1.7l with all new fuel lines, car ran a little rough and almost stalled out when I let off the gas when revving it in neutral. First thing I did was replace the strainer. Fuel filter, and cleaned the tank and put new gas in it. Yesterday i started it up and it ran just fine! Turned it over today and i have no fuel pressure at the fuel rail. I turn the key and hear the pump working, but it won't start. Changed fuel pressure regulator, no dice. Also the clear lines near the battery that run into the engine bay has an air bubble in it and I noticed there is no fuel moving through that either. I'm completely stumped if anyone has an idea. I'd swap the filter but I put in a brand new one yesterday and it worked perfect then.

Could my fuel pump be bad even though I hear it working? The fuel pressure was staying at just under 40psi yesterday and randomly dropping to 20psi, even lower when I let off the gas pedal.

Any insight is appreciated

Your fuel pressure should be be around 28-30 lbs. Are you using a 3 port pump?

Yup, original fuel pump

One of the lines underneath the tank might be kinked. I had the tank in and out 4 or 5 times trying to get the lines to sit just right until I realized there’s an access hole underneath the car on the passenger side. Take off the pan for the steering rack (4 bolts) to access the access hole. Should be easy to at least check this way.

I'll double check but I just replaced those lines from the access hole underneath yesterday as well

Problem can be the pump is on its way out,they can power up and buzz away but not pump anything or not enough to maintain system pressure.
This is a common problem with Mk2 Golfs also ,generally they get weaker quickly after becoming noisy and the car will buck and splutter on throttle and then will stall and not start again.

I believe you are right. All signs have currently pointed to it. Just did not want to believe