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BRGcoopahS
10-03-2012, 04:53 AM
Lately when you start the car in the morning and have your foot on the brake, the pedal goes down and then you have to pump it a few times to get it back to normal. What could be the problem?

llll1l1ll
10-03-2012, 06:16 AM
It could be that the seals in the master cylinder are wearing out, but I wouldn't suspect that to be happening this early in the game. That's like 160K plus wear issues. Maybe there's a leak in the system somewhere? I would keep an eye out for fluid leakage.

Bimmernut2
10-03-2012, 09:15 AM
You might want to check your brake boosters vacuum hose that runs from the booster to the DISA valve. Also, there's a check valve at the end that attach's to the Booster that might be bad. Sounds like you're loosing the vacuum while it's sitting. If it's not that, the master brake cylinder will do this if it has an internal leak. You can test this by just putting your foot on the brake pedal. If it moves toward the floor very slowly, it needs replacing. You can pump the brake again & it will stop at the top & then slowly drift toward the floor. How many miles on the car?
Here's a link to my last post on the collapsed brake hose. Let me know if you need a picture.
http://www.zhpmafia.com/forums/showthread.php?8039-Collapsed-brake-booster-hose-issue.-Is-this-common

Also, as mentioned by above, check your brake fluid level. You could just be low on fluid; however, you should see a warning light come up on that.

BRGcoopahS
10-03-2012, 09:37 AM
I repaired the DISA on the car a month or so ago and I dont remember removing any vacuum hoses when I took it out. I'll check that out. Car has 64k

edit: checked the hose. Im not quite sure what a collapsed hose is but it does have a flat spot sorta right above the disa. I'm assuming that means its collapsed? I actually checked the "show off your engine bay" thread and it looks like alot of them are flat in the same spot.

BRGcoopahS
10-05-2012, 07:41 PM
bump

Just trying to figure out what the problem could be. I'm assuming it isnt the master cylinder since its only got 64k. So it could either be the vacuum hose coming out of the master cylinder, or the check valve.... or a leak.

I havent tested it out myself since it is (still) my fathers car. Hopefully tomorrow I can see. I dont think its the cylinder since the brakes go back to normal after pumping it. Otherwise it would be constantly going to the floor, right?

az3579
10-06-2012, 04:54 AM
Do you have this problem while driving after you've pumped the brakes a few times? If not, I don't think you have anything to worry about. The system needs to be pressurized before normal operation could be achieved. How many times do you have to pump?


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BRGcoopahS
10-09-2012, 07:11 AM
I havent driven the car in a few weeks so I dont know specifically. I think its only a few times and I know it doesnt happen while driving.

derbo
10-09-2012, 09:34 AM
rebleed the brakes? Couldn't hurt.

BRGcoopahS
10-10-2012, 04:32 PM
lol so today he tells me the pedal was the exact opposite before starting it. It was raised up more and very stiff. I told him when you pump the brakes on a car that isnt running that will happen. He didnt pump the brakes though.