After recently changing my brake pads and bleeding the system correctly, I noticed that the pedal is stiff when the car is off and really loose when the car is running. The brakes don’t work at all. Anyone know what is causing this?

 

Sounds like your brake booster is working. Have you checked your brake pedal free play as per the factory service manual? This is absolutely critical in having these brakes work properly on these cars.

 

Air in the system. The brake booster only works when engine is on. You should bleed the system again.