Brake paddle hard before engine start

[whitelance78]

Anyone knows what is the problem? Before i start the car in the morning, i got to step on the brake paddle while pressing the ignition button right? I noticed recently the paddle becomes hard, can't step down fully. But after starting the engine, I am able to press down the paddle as brake works as normal.

I noticed this problem occur only if i leave the car unused for 12 hours. If its like 5-6 hours later after i last used the car, it doesn't have the paddle 'hard' problem when i start the engine.

 

[sszone]

Re: Brake paddle hard before engine start

probably a leak in your vacuum hose bro

 

[156F1]

Re: Brake paddle hard before engine start

Thought it is quite normal. The vacuum after engine off would take some time to lose its "strength". Hence, braking system is not assisted and pedal would feel hard. Don't think you need to worry too much.

 

[eddienike]

Re: Brake paddle hard before engine start

Thought it is quite normal. The vacuum after engine off would take some time to lose its "strength". Hence, braking system is not assisted and pedal would feel hard. Don't think you need to worry too much.

+1

Yes is normal. Confirmed with few workshop including site sponsor.

 

[Simone]

Re: Brake paddle hard before engine start

Hi all
I encounter the same problem, but feel more relief now thanks for the information.Cheers :laughlik:

 

[cyrus271]

Re: Brake paddle hard before engine start

Hi all
I encounter the same problem, but feel more relief now thanks for the information.Cheers :laughlik:

have the same issue with my 07 E90 - and also found sometimes engine does not fire on the first crank. Thought maybe electronic gremlins... like how my electric steering once failed to engage when i pulled out my key, leading to me not being able to start the car until the tow truck came (which made me feel really dumb). Fingers crossed and hope this is not the start of something.

 

[detach8]

Re: Brake paddle hard before engine start

vacuum leak likely, better get it checked. theres a one-way valve that holds the vacuum pressure...

 

[SeeStars]

Re: Brake paddle hard before engine start

after u insert yr key, radio starts and before u press the push start button to start the engine, shd yr brake paddle stay "hard" or able to step downwards?
Not able to crank the engine at first attempt sometimes and have to pull out my key for several tries. When the brake paddles stays "hard" I am not able to start engine. When able to step downwards, engine starts, is this normal?

 

[eddienike]

Re: Brake paddle hard before engine start

after u insert yr key, radio starts and before u press the push start button to start the engine, shd yr brake paddle stay "hard" or able to step downwards?
Not able to crank the engine at first attempt sometimes and have to pull out my key for several tries. When the brake paddles stays "hard" I am not able to start engine. When able to step downwards, engine starts, is this normal?

How long is your battery? I used to have the similar problem, very frequent my first attempt cannot crank the car. After change the battery, now even it is hard, I jus need to step a little the car can be crank. No more second or third attemps.

Hopefully, your case is not starter motor or footwell module faulty which cost even more than the battery to replace.

 

[avenue]

Re: Brake paddle hard before engine start

I also got the same prob on my 9mth old ride. Sent back to PML twice...2nd time then they rectified it..but now after a few mths, prob recently come back again though intermittent...its a vacuum leak. I can still start the car although the pedal is hard..just step harder loh...hehe..

 

[R2D]

Re: Brake paddle hard before engine start

Hi, just to add.

The car uses the brake fluid pressure sensors on the master pump to read the brake prressure. Once the pressure crosses a certain pressure, the ABS system give the go ahead for the ECU to start the car. This is a safety feature to prevent the car from surging ahead for any unforseen reason.

If you find the brake pedal unusually hard the moment you enter the car and try and start the car, its a sign that there is a vacuum leak. The leak can happen from either the check valve on the plastic pipe between the booster and the vacuum pump or within the booster itself. Both of these can be faulty ecpecially in the 4cyl n46 engines as the vacuum pump sometimes contaminates the air line with engine oil and this screws up the rubber seals within the check valve and the booster.

cheers