Replaced the brake fluid this morning. Whilst using a pressure bleeder, when I open the rear nipples, nothing come out… I had to pump the brakes to get the fluid flowing. No pressure loss from the bleeder or anything like that. Managed to get the job done but expected the pressure bleeder to force the fluid through without having to pump the brakes; As it’s done with every other car I’ve used it on. Just curious if anyone has had this before or if this is normal for the Z4?