Replaced Fuel Pressure Regulator-Worse than before

Hello experts,

The engine of my 1998 Lumina 3.1 was idling rough. I found out it was a bad Fuel Pressure Regulator. After I replaced it, the engine runs worse than before. It even runs when I just put a gear in without accelerating. I also have no power brake in idle. I did not unplug any major wires and I put everything back where it was before. Battery was off the whole time.

Thank you for any help.

UPDATE: I thought, what the heck, it can go worse, and drove around, shiftin all gears. Now the brakes are back again and I can shift very well, but the idle is very high in park and stop. May someone can explain me this?

Did you replace the regulator because there was fuel in the vac line?

Have you checked for a vac leak?

Yes I did checked for a vac leak. There is no leak anymore.

If you lost the power brake you have a vac leak somewhere or the engine is running so poorly there is low vacuum, keep looking for both issues.

Yeah sure sounds like its sucking air someplace....