2003 North American D2

While driving, I'm getting a noise of air being released when I push down on the brake pedal. It is releasing pressure in the system and the brakes are not working very well.

I pulled back the dust shield that covers the area between the firewall and where the brake pedal connects to the master cylinder.

I'm looking on-line for the parts. It seems it may be the brake booster or the could it be master assembly. Both come with an O-ring where they connect. Could the O-ring be changed to solve the leak or more likely the brake booster needs to be replaced?

The sound is defiantly coming from inside and you can not hear anything from the engine bay. Of course the engine needs to be on to get the feedback.

thanks,

 

Probably the booster, they develop a leak in the diaphragm.

 

Thank you Extinct, your suggestion was correct.

Tarheel Rover parts is not too far away from me and I was able to get a brake booster from him. I got the master cylinder as well from his same donor D2. I did not want to have any issues with the O-rings by separating them.

Lot's of bleeding afterward but now the brakes feel better than before.