The problem when I try and press the brake peddle to then press the start button the peddle will not move and there for can't start the car, the dash lights up but it wont start the engine, I eventually found by pressing very hard on the brake peddle it finally had movement and now was able to push the button to start the engine, this is a hit and miss problem, it has happened to me only 5 or 6 times and maybe weeks apart before it happens again, any suggestions

The only suggestion I would have is have the dealer check it out. I do not have to press down on my brake pedal very hard to activate the start switch.

Go to a gym and start lifting some weights so you can easily press the brake pedal harder? Seriously, I've miss timed my foot getting to the brake pedal before I hit the start button a couple times, but that was just my own fault. Your saying you can't push the brake pedal to engage the safety switch and allow the starting sequence? Have you taken it in to the dealer and see what they had to say about it?

You are somehow losing vacuum in your brake booster. Generally, you can get one or two assisted pushes after the engine is off. Most likely, you are shutting off your car and continuing to depress the brake pedal (consciously or unconsciously). Therefore there is no vaccum left to assist the brake being pushed when you go to restart the vehicle.

For anyone else that would like to experience what I believe J Jones is describing, simply turn off your car and pump your brake pedal. You will note it gets more and more difficult until all of the vacuum assist is depleted. You can and will be able to start your car by FIRMLY depressing the brake pedal.

Let us know if this helps.

Just to check my own curiosity, I went out to my car, pumped the brakes like 15 or 20 times, and yes, it got a bit firmer, but was still able to move the brake pedal about 2-3 inches with little more then the weight of my foot, and started the car with no problem. I did it several times with varying amounts of brake pumping and they all equalled the same result.

Its hard to say.

J Jones' may be describing "very hard" because it is unusual for him/her to have to apply more effort than usual. Your description of the same event may be significantly different ("weight of my foot"). Or maybe the difference is the sublte nuances of a vehicle build from the factory, where your brake pedal push rod may be adjusted to have more leverage than J Jones. On the same note it could be difference of the adjustment of the safety switch. I can only speculate on the cause, but the symptoms sound like a text book loss of vacuum.

Regardless, 15-20 times is significant and I'm quite surprised. Were you pushing slowly all the way down until the stopping point and then fully releasing, or merely quick pumping? (I realize I may have used the wrong terminology above.)

Full pushes, as far as the system pressure would allow. You can feel when the booster looses it's assistance, but I didn't really feel it prevented nor really offered any assistance for the first 2-3 inches of travel anyway.

OK I tried the brake thing this morning after car sat all night. I hit the pedal kind firmly once and it was soft. Next time I hit the pedal was very stiff, but I was able to start the car ok. Tried again and after one punch pedal was stiff but waited a few sec and it had more give to it again. At any rate it never did prevent me from starting the engine.

It did not prevent the original poster from starting the vehicle either. That's what makes me believe it was a result of simply depressing the brake after the engine was turned off.

We may never know since the J Jones has since gone silent...

He said he couldn't start the car when the pedal was stiff. Mine did start with stiff pedal.



I hope nothing has happened to him.

Maybe the op is stuck in the car because they couldn't pull the door lever open?

That's a whole different thread.