Brake Pedal SUPER HARD to press after boosting

[FSRRM]

Okay, so I'm doing my own thing, logging, tuning, logging, tuning.

But all of a sudden after a HARD BOOSTING I am unable to press the brake pedal for about 3 seconds then it gets soft and I can brake again, IT'S SO SCARY and DANGEROUS.

Wondering if anyone could shed me some light.

Car: Mazdaspeed 3 2008 Gen1

It's definitely not brake fade I know what that's like


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[Crarrs]

Bad check valve in the vacuum circuit to your brake booster.

[Djohns]

Your car loves the feeling of going fast so much it will do anything to not stop?

[FSRRM]

Originally Posted by Crarrs Bad check valve in the vacuum circuit to your brake booster.

That makes a lot of sense, I'm going to get that replaced asap, I'll let you know when I replace it.

Thanks for your help


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[FSRRM]

Where would I find the one way check valve?


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[Crarrs]

Try the bulging part of the vacuum hose coming off the intake manifold, next to the HPFP in your photo. If not there, maybe behind the heat shield. I don't know anything about how that hose is routed on a RHD car.

[FSRRM]

Originally Posted by Crarrs Try the bulging part of the vacuum hose coming off the intake manifold, next to the HPFP in your photo. If not there, maybe behind the heat shield. I don't know anything about how that hose is routed on a RHD car.

I couldn't see any valve in the intake side of the vacuum line, checked he line next to the HPFP.

Could you please send me a photo of what I am looking for or is it really different


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[FSRRM]

Would this be it? I found this part on my Brake Booster


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[Crarrs]

You're VIP, so you can download the full service manual from this site. Start there.

[FSRRM]

Originally Posted by Crarrs You're VIP, so you can download the full service manual from this site. Start there.

Didn't even know that existed, only donated because I appreciated the help with my intank Methanol tuning. Cheers!


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[FSRRM]

Sooooo I found the Check Valve, I can blow through and back in.

Called Mazda parts division and he said yeap that's the check valve.

So I'm ordering the part now to fit, also I put a quick photo together what it looks like


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[paukacang]

Originally Posted by FSRRM Sooooo I found the Check Valve, I can blow through and back in. Called Mazda parts division and he said yeap that's the check valve. So I'm ordering the part now to fit, also I put a quick photo together what it looks like Sent from my iPhone using Tapatalk

hello
My ms6 got brake problem as u mention above. may i know part no for CHECK VALVE

[Fstrnyou]

Google it. It's not hard.

[hichamaziz]

hi all i love mazda cars .

[Djohns]

Originally Posted by hichamaziz hi all i love mazda cars .

Are you that bored you have nothing better to do but troll?

[5doorsoffury]

Originally Posted by hichamaziz hi all i love mazda cars .

And i love cumming on your mom's face but you hear me bragging about it in a fucking brake issue thread.

well now you have!

EDIT: God dammit im as brown as the mustache i gave your mom fuck!!!!

[Djohns]

Originally Posted by 5doorsoffury And i love cumming on your mom's face but you hear me bragging about it in a fucking brake issue thread. well now you have! EDIT: God dammit im as brown as the mustache i gave your mom fuck!!!!

I actually did hear about it prior to this situation thank you very much.

[shamie]

Originally Posted by FSRRM Sooooo I found the Check Valve, I can blow through and back in. Called Mazda parts division and he said yeap that's the check valve. So I'm ordering the part now to fit, also I put a quick photo together what it looks like Sent from my iPhone using Tapatalk

So what was the part number you ordered?

[MSMS3]

Originally Posted by Djohns Are you that bored you have nothing better to do but troll?

Don't feed the trolls. They just get bigger.

[Fstrnyou]

It's okay now. Troll haz been banned.

[FSRRM]

Originally Posted by shamie So what was the part number you ordered?

Check your brake booster, if it has a check valve like this then it will be that part, I am working on getting the number for you as I didn't get it in a pretty mazda wrapping with model number on it, I just ask for the part, it's ex japan and just gets shipped to me, I will get back to you on this as I have already ordered another one for a user that's having the same issue


EDIT: Darn, I am now a brownie again >_>

[shamie]

Yes my booster has a valve like that - I just can't find the part #.

[FSRRM]

Originally Posted by shamie Yes my booster has a valve like that - I just can't find the part #.

parts coming from Japan so I will update you when the box comes

[shamie]

Get the number yet?

Is it E112-43-826 by chance?

[FSRRM]

Sorry about the delay, this is the part I got from Mazda and is the part that goes into the brake booster

[darkmx-6]

Did it fix your problem?

I have the same problem so I added an inline check valve that I got from Treadstone and it's still doing the same thing...

I guess I have to remove the old defective one?

[MichaelAress]

Air in the system would result in a spongy or soft pedal that goes to the floor. You can always try to bleed it more. I always do when something is up and 9 out of 10 times it fixes it. Also as Paul said you will be able to stop a vehicle without the booster working, you just need to press harder.

How far does the pedal move before it becomes extremely stiff?