Where would there be a vacuum leak in the brake system?

[rothsean]

I am thinking that I have a vacuum leak when I press the brakes. Where would it leak from? Where can I check?

The engine idles rough when I have the brakes pressed on.

[LEVY]

I believe you have a defective brake booster.

If you notice change on engine RPM when you hit the brake, then no doubt you have a bad brake booster.


LEVY

[rothsean]

I believe you have a defective brake booster.

If you notice change on engine RPM when you hit the brake, then no doubt you have a bad brake booster.


LEVY

Where is the brake booster?

[Mike C.]

Where is the brake booster?

Open your trunk, remove your carpet.

Remove the access panel for your brake fluid reservoir. At the back of the reservoir, you will see a biiig round thing that the brake master cylinder bolts to... That be your brake booster. Looks like a big black puck.

[DMCMW Dave]

http://store.delorean.com/c-356-6-3-0-master-cylinderpower-unit.aspx

#10 on the drawing.