I'm wondering if there is such a thing as a check valve somewhere between the brake vacume line and the brake booster

I have this issue where when I go into boost and quickly press on the brakes the brake pedal is hard for a second normally I've gotten used to it


I tried buying what appears to be a filter that goes on the booster but it was just that a filter air comes and goes both ways


So in essence my brake booster is acting as another area which needs to be filled with air from turbo thus adding to turbo lag

So I'm wondering if there is such a part

Since I bought my car as a shell which came with nothing in the engine bay I do not know , I remember looking at the fsm and finding that filter hose that goes to the booster and I thought that was the root of all evil but I was wrong

So maybe someone has an idea ?

 

In the factory rubber hose attached to the booster nipple, there is a check valve. It is actually inside the hose, and only looks like a little bulge from the outside.

 

Yea will will have to remove that hose and verify that the checkvalve within is actually working properly.

 

Mazda did a brake hose recall kit in the '90s. The original hoses had the check valve over on the passenger side of the engine, the heat would cook it and you'd have the rock hard pedal.

The kit has 2 new hoses and has the check valve on the driver's side. You most likely have the newer hoses, but you can just get that kit (which is quite cheap, I think like $20 or something) and have nice new hoses.

Ray can get that for you no problem. I think it's cheaper to get the kit than to just buy the individual hoses.

I would get the Mazda parts instead of trying to find or make something - this could be potentially dangerous.

Dale

 

Also, no need to remove the check valve to verify it works. Just remove the hose that its enclosed in and blow through both ends. Should blow one way but not the other.

Matt