[aiz121]

Hi guys!

I've been having problems with my brakes after starting the car for the first time in the morning. The brake pedal is stiff and it only goes about halfway. I researched on this and found that it might have something to do with the brake booster losing vacuum.

The car is 06 civic sedan, with K&N SRI installed. I just brought it to a mechanic and they said that its because of the SRI and the only solution to this is to put the stock intake back in.

Is this normal for everyone who has a SRI in their car? Or is it due to other problems thats not related to the SRI?

Thanks!

 

[ArmyofOne]

:facepalm:

I am sorry, it is not you im facepalming. It is the world. Thousands of people (including myself @ 1 point) had/have SRI's. This is not a normal occurence to my knowledge. Is it affecting your braking performance (they still work, right)?

How many miles does your car have?

It seems its temperature related, so I would start with a fluid change before jumping to parts replacement...but a sure-fire way to tell is to throw the stock intake back on and see if it does fix the problem. It is very unlikely that the cause is the intake though. More than likely the fluid has reached the end of its useful life.

 

[sick_civic]

cool ******* math..

some how a engine part effect's your breaking system...i didn't know civic's had their own engine breaking control.

Fail.

 

[ArmyofOne]

cool ******* math..

some how a engine part effect's your breaking system...i didn't know civic's had their own engine breaking control.

Fail.

Some cars DO infact integrate the intake system with the brake booster via vacuum lines. But this is usually done at the intake manifold or TB...NOT from the intake itself. And brakes do use the Vacuum system in most cars now to assist in braking.


BUT...I have never seen a Short-Ram cause it, unless there was a leak somewhere in the vac system.

 

[slow4drsi]

almost all the guys are stiff in the morning. it's normal man.

 

[BigT]

Is this only before starting the car, or does it remain stiff for a while after starting the car?

Either way, it's not directly related to the intake. The only possible relation would be if the intake is physically interfereing with a vacuum line or something like that. The brake booster operates off manifold vacuum, which is taken after the throttle plate and is affected very little by the intake.

 

[ArmyofOne]

almost all the guys are stiff in the morning. it's normal man.

:facepalm::facepalm: That was bad. :clapping: .

The only possible relation would be if the intake is physically interfereing with a vacuum line or something like that. The brake booster operates off manifold vacuum, which is taken after the throttle plate and is affected very little by the intake.

Thanks! Thats what I was trying to say. I have always been a better learn-er than a teacher.

OP, change your fluid. If you cant/dont want to, your dealer (NOT WAL MART, JUST BRAKES, MIDAS OR THE "MECHANIC" YOU TOOK IT TO BEFORE) should be able to do this for you for around $100.

 

[aiz121]

almost all the guys are stiff in the morning. it's normal man.

ROFL!! Glad to know mine is working perfectly. :dance:

Is this only before starting the car, or does it remain stiff for a while after starting the car?

Either way, it's not directly related to the intake. The only possible relation would be if the intake is physically interfereing with a vacuum line or something like that. The brake booster operates off manifold vacuum, which is taken after the throttle plate and is affected very little by the intake.

Its only after the car has started. After about 2 mins of driving, braking goes back to normal. I didn't really understand your explanation. Does it mean that in our civics, the intake is not related to the brake booster? Sorry for being a noob. :redface:

OP, change your fluid. If you cant/dont want to, your dealer (NOT WAL MART, JUST BRAKES, MIDAS OR THE "MECHANIC" YOU TOOK IT TO BEFORE) should be able to do this for you for around $100.

So its most likely the brake fluids thats causing this problem then? The car has about 55,000 km (34,175 miles if ur american. :wigglesmiley

 

[splew]

Some cars DO infact integrate the intake system with the brake booster via vacuum lines. But this is usually done at the intake manifold or TB...NOT from the intake itself. And brakes do use the Vacuum system in most cars now to assist in braking.


BUT...I have never seen a Short-Ram cause it, unless there was a leak somewhere in the vac system.

:yeahthat: Vacuum brake boosters use manifold vacuum (aka after the throttle body), so I can't think of any way that installing an intake (which just replaces parts before the throttle body) would affect your vacuum assist.

almost all the guys are stiff in the morning. it's normal man.

Beat me to it.

 

[BigT]

I didn't really understand your explanation. Does it mean that in our civics, the intake is not related to the brake booster? Sorry for being a noob. :redface:

Correct, your short-ram intake is not related to the brake booster, and will not be causing this issue.

So its most likely the brake fluids thats causing this problem then? The car has about 55,000 km (34,175 miles if ur american. :wigglesmiley

Possibly. However, the fact is, most people don't change their brake fluid often, if at all. Stiff brake pedal isn't a common symptom of bad brake fluid. Brake fluid absorbs water over time. This can potentially cause air pockets due to vaporization of that water (causing a softer pedal during extended periods of heavy braking). But more importantly, this water can cause corrosion and damage to brake components. If it caused a temporary stiff pedal when cold it would be a first I've heard of it, though that's far from saying it couldn't happen.

 

[BigT]

Next time you drive the car, if the brakes are working fine when you shut the car off try pumping the brakes a few times once you shut the engine off. This will bleed the remaining vacuum off and the pedal will stiffen up. Once you pump the brakes enough that they stiffen up compare that feeling to the feeling when you start the car and have the issue. If it's exactly the same, then the issue you are having is likely that you don't have any vacuum boost (not related to fluid).

That is only the first step. The next is figuring out why you don't have any vacuum boost only for the first couple minutes.

 

[ArmyofOne]

ROFL!! Glad to know mine is working perfectly. :dance:



Its only after the car has started. After about 2 mins of driving, braking goes back to normal. I didn't really understand your explanation. Does it mean that in our civics, the intake is not related to the brake booster? Sorry for being a noob. :redface:



So its most likely the brake fluids thats causing this problem then? The car has about 55,000 km (34,175 miles if ur american. :wigglesmiley

At that mileage, not likely your fluid is bad either, though it could be the age.

I didn't really understand your explanation. Does it mean that in our civics, the intake is not related to the brake booster? Sorry for being a noob. :redface:

Correct, your short-ram intake is not related to the brake booster, and will not be causing this issue.

So its most likely the brake fluids thats causing this problem then? The car has about 55,000 km (34,175 miles if ur american. :wigglesmiley

Possibly. However, the fact is, most people don't change their brake fluid often, if at all. Stiff brake pedal isn't a common symptom of bad brake fluid. Brake fluid absorbs water over time. This can potentially cause air pockets due to vaporization of that water (causing a softer pedal during extended periods of heavy braking). But more importantly, this water can cause corrosion and damage to brake components. If it caused a temporary stiff pedal when cold it would be a first I've heard of it, though that's far from saying it couldn't happen.

:yeahthat: .

 

[aiz121]

Next time you drive the car, if the brakes are working fine when you shut the car off try pumping the brakes a few times once you shut the engine off. This will bleed the remaining vacuum off and the pedal will stiffen up. Once you pump the brakes enough that they stiffen up compare that feeling to the feeling when you start the car and have the issue. If it's exactly the same, then the issue you are having is likely that you don't have any vacuum boost (not related to fluid).

That is only the first step. The next is figuring out why you don't have any vacuum boost only for the first couple minutes.

Ok, I've tried your diagnostic test, and yeah, it does feel similar, but less stiff in the morning compared to vacuum-bled when the engine isn't running.

Knowing this, what should my next move be? Should I bring it to the dealer? What if they blame it on the SRI?

 

[ArmyofOne]

if you have the factory intake, it takes less than 30 mins to put in, if you have never done it.

If you dont, they should not say anything about just an intake.

 

[m85476585]

Bringing back an old thread, but I'm having this problem too, and I'm wondering if anyone has found a solution? It looks like there's a TSB 07-077 BRAKE PEDAL CAN FEEL HARD DURING THE FIRST COUPLE OF BRAKE APPLICATIONS, USUALLY IN THE MORNING WHEN THE AMBIENT TEMPERATURE IS COLD.

Can anyone get a copy of this TSB for me?

My car is all stock, and I recently had the brake fluid changed. I can't remember if I had this problem before the fluid change, but I think I did a few times.

 

[m85476585]

I tested pumping the brakes until the reserve boost is gone, putting my foot on the pedal, and starting the car, and it works as expected. When the car starts, the pedal softens up in a second because of the power brake boost building pressure (or vacuum).

Last time I had a problem was a few days ago. I had backed out of a parking spot and started driving forward. It was shortly after I started driving forward that the brakes felt stiff (or didn't really stop the car like they should). I didn't notice it in reverse because it didn't take much braking to stop the car. The parking spot was nearly level and it was warm out (70-80F) so nothing unusual there.

I don't drive every day, so it's hard to say how frequently it happens. I drive every few days on average, so I don't think I'm letting the car sit too long. Last time I had the problem the car had been parked for two days.

 

[Midgear]

I'm gonna revive this rather than starting a new thread-

This last week I've noticed my brake pedal being hard as a rock when I first get in the car. that's the first pedal I hit, then clutch, then fire the car up. the second the car fires, the pedal drops and the brakes function normally. plenty of stopping power and normal feel as the motor is running. It's only when the car sits- seems the brake booster is loosing all its vacuum. Usually you'd have to pump the brake pedal a few times to stiffen it up with the motor off. when I first hop in and press the pedal, it feels like someone has pumped it quite a bit while its been sitting.

has anyone had any further issues from this or a proper diagnosis?