Alfa Romeo Forums banner

1 - 5 of 5 Posts

·
Registered
Joined
·
115 Posts
Discussion Starter #1
Recently got my new to me alfa spider on the road and I am having a problem with the brake booster. Sometimes I have power brakes and other times I do not. The pedal does go lower when I shut the car down like it is suppose to. I would think that if the booster was bad I would never have the power setup working. Any ideas?
 

·
Super Moderator
Joined
·
11,220 Posts
Intermittent problems are harder to diagnose than things that are simply dead. You might have a flakey vacuum connection somewhere: cracked hose, cracked connector on booster, bad one-way valve in manifold, etc. I'd start by inspecting all those components for cracks, loose connections, etc. After that, you might try wiggling the hose while the engine is running to try to find a place that produces a sucking sound.

I guess it's possible that something internal to the booster is intermittent. Don't know how you would diagnose that, other than rebuilding/replacing the booster and hoping that fixes it. So I'd try this last.

Does the engine run any differently when the booster isn't working? A major vacuum leak would affect the idle.
 

·
But Mad North-Northwest
Joined
·
11,023 Posts
Could be a bad check valve and/or a leaking booster valve. Does the booster hold vacuum after you shut the car off? If no, check if the metal check valve at the intake manifold is working.

If it's not holding vacuum and the check valve is good, probably a leaky valve in the booster.
 

·
Registered
Joined
·
115 Posts
Discussion Starter #4
Thanks guys for the tips. I haven't had this issue before. Either the booster works or it does not.
 

·
Registered
what part?
Joined
·
10,113 Posts
try this,, plug the hose from the manifold to the booster,, so the hose only is connected to the intake manifold, plug that hose drive the car.. you might find out that stopping a light weight car with 4 disk brakes is not that hard.. it will be a adjustment in foot pressure, but not hard to get use too
 
1 - 5 of 5 Posts
Top