maybe someone can help me ... i have a 92 240sx , with the z32 brake upgrade, and i have a new master cylinder and a used z32 brake booster, and my car was parked for a while and when i went to drive it the brake pedal was rock hard... so i went for a drive and i slammed on them .. and they locked up and stayed locked up, i had to release the pressure to move again... and suggestions.. everything is brand new plz help

 

Air in the lines, proportioning valve? stuck piston on the caliper?

 

just get the calipers rebuilt at good year or pep boys

 

Yeah, that is typically a seized piston or several

 

sounds like you have a bad booster

 

yeaup mine just started action up time for New Booster.

 

Yeah...definitely a possibility. The only thing about this is, if the brakes are not releasing, it probably is not the booster, or not just the booster

 

Touche...........