I just bought my 76 280z. I think there might be a problem with my brake booster it idles perfect until you press the brakes once you do so the car proceeds to drop in idle and sputter but not die all the way any suggestions?

 

 

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Sounds like a vacuum leak in the booster, unmetered air is coming in from the booster that the Air Flow Meter, AFM doesn't know about and can't compensate for.  There some experts here that can walk you through the process.

Plug the line going to the brake booster with a bolt and clamp and see if that symptom stops

That's a classic bad booster sign.  If the engine is running a bit rich the idle speed will go up.  Sounds like your engine is tuned about right so the idle speed drops.

The boosters usually go bad when the master cylinder leaks.  So watch out for brake fluid in the booster.  It will drip on to your paint and stain it.

Boosters are getting harder to find also.

Power brake exchange in San Jose California can rebuild them, I had mine done by them;

 if you end up using them have them power coat the booster, they run it through a bead blaster, it should be an additional $20.
 

im not sure if DIY kits are available... I wonder where PBE gets theirs....

Edited March 7, 20205 yr by heyitsrama

On 3/7/2020 at 12:32 PM, heyitsrama said:

Power brake exchange in San Jose California can rebuild them, I had mine done by them;

 if you end up using them have them power coat the booster, they run it through a bead blaster, it should be an additional $20.
 

im not sure if DIY kits are available... I wonder where PBE gets theirs....

Do you remember about how much you paid?

Just got mine back from them. Had no idea they offered powder coating. Man.......

On 4/23/2020 at 1:42 PM, Yarb said:

Just got mine back from them. Had no idea they offered powder coating. Man.......

dont go installing it on the car without painting it, its gonna look like $^!# after it starts to rust!

Grab flat-black (at least thats what i like) 7776 rustolium and some primer. 2 coats primer, 3 coats of paint.

Might even want to grab something that's resistant to brake fluid, (caliper paint?) powder coating is not.

On 4/23/2020 at 1:00 PM, rcv said:

Do you remember about how much you paid?

total  w/ tax: $125.88 without powdercoating

Sounds about right.