Fueling & Injection - Fuel pressure regulator gone bad?

I recently replaced my fuel pump (walbro) and after the install my car started acting weird. If I let it sit overnight, it fires right up in the morning. But throughout the day if it sits for an hour or so, it turns over a few times before it fires up. Sometimes more than a few times. The battery is fine, alternator to.

Any ideas?

It is normal. The stock pump has a check valve in it that keeps the rail pressurized. The Walbro does not. Sometimes you have to turn the key on, then off, then on again (I monitor it on my gauge) for full pressure and a clean start.

I highly recommend a fuel pressure gauge though. My stock regulator was giving me 76 psi with the Walbro. Some regulators go low, some go high, and some work just fine after the pump swap. Its just nice to know exactly what its doing.