Weird braking sensation on pedal

[earthrealm]

I tested mine today, and I can confirm that the pump does not come on when the ignition is off. I pumped the brakes for about a minute with the ignition off, and the pump never came on.

The pump in mine runs for 1-2 seconds every other time I press the brakes. There's a slight buzzing sound, but I don't know if it's normal.

pls help me do the following:
turn your ignition on, and observe the pump for 1 to 2 mins, if it doent kick in, you may depress the brake pedal, and observe if the pump will kick in..if it does kick in...then good...leave it again for 1 to 5mins, and see if it will kick in again by itself without you engaging the brake...[you do all this with the ignition on, and car off]
[MENTION=66389]BlackWorksInc[/MENTION] yeah, i understand my MC pump might be going bad, am just trying to see if i can figure out the root cause, cos its either a leak in the system...or air in the system that would be causing the pump to engage so very often, thereby shortening its life and leading to early failure...........if we can isloate the cause of the pump kicking in so very often, then forum members with similar symptoms as mine could take a pre emptive measure in stopping the root cause

 

[m85476585]

[MENTION=78511]earthrealm[/MENTION],

I did a quick test when I got home today. The car was fully warmed up, and it was 32 degrees out (I doubt it's relevant). I parked, turned off the engine, and turned the ignition back to on. I pressed the brake lightly to make sure the pump would still come on, and it did. I waited 5 minutes and the pump didn't come on. After 5 minutes I pressed the brake lightly, and the pump still didn't come on. I pressed it again, and the pump came on as expected. It comes on every other time I use the brakes.

I would test longer, but I was bored of sitting there. Next time I'm working on it I might leave it on for a while and see if it ever comes on. I don't think I would notice it while driving unless my foot was on the brake pedal, it's not very loud but there's just a slight hum and some vibration through the brake pedal. It's easy to hear if I'm stopped.

I hope this helps!

 

[earthrealm]

[MENTION=78511]earthrealm[/MENTION],

I did a quick test when I got home today. The car was fully warmed up, and it was 32 degrees out (I doubt it's relevant). I parked, turned off the engine, and turned the ignition back to on. I pressed the brake lightly to make sure the pump would still come on, and it did. I waited 5 minutes and the pump didn't come on. After 5 minutes I pressed the brake lightly, and the pump still didn't come on. I pressed it again, and the pump came on as expected. It comes on every other time I use the brakes.

I would test longer, but I was bored of sitting there. Next time I'm working on it I might leave it on for a while and see if it ever comes on. I don't think I would notice it while driving unless my foot was on the brake pedal, it's not very loud but there's just a slight hum and some vibration through the brake pedal. It's easy to hear if I'm stopped.

I hope this helps!

Yeah!...
This is exactly what i ..thanks.
I now understand the system better...i judt need to understand why mine is acting the way it is...all clues point towards a leak in the system.....i dont think having air in the system will cause such problems