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Discussion Starter #1
I just replaced my front brake pads and rotors. I followed the directions as found on this and other VW/Audi sites and found it was not that difficult to do. I've done the rear brakes twice without issue but this was my first attempt at the front ones. Everything went in fine however when I went to test the brakes I found that the pedal goes almost to the floor and that I can only get braking power if I pump the brake pedal several times. My brake fluid reservoir is full, or so it seems. I know that I lost some fluid when I took the old brakes off as they say you should loosen the fluid cover to reduce the pressure when you force the brake piston closed to get it back on the rotor.

Any idea what may be wrong and how I can fix it?

Appreciate it.

Mark
 

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I know that I lost some fluid when I took the old brakes off as they say you should loosen the fluid cover to reduce the pressure when you force the brake piston closed to get it back on the rotor.
Did you open the bleeder on the calipers?

Or just remove the cap from the reservoir?

If you just removed the cap from the reservoir why do you say you lost fluid?

Obviously you may have a bit more pedal travel at first until you get the piston and the pads pushed out into place.

Is your brake pedal holding firmly now? Or is it fading as you hold pressure on the pedal?

I would check the fluid level in the reservoir and bleed the fronts if you opened the bleeder valves.
 

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If you didn't open the bleeder valves you pushed dirty/burnt fluid back into the ABS and MC; I would bleed at least the front brakes.
 

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Discussion Starter #4
I did not bleed from the calipers. I simply loosened the cover to the reservoir to relieve pressure when I pushed the piston in to get the pads on. Some fluid spilled out over the top of the reservoir but not a lot. At any rate I think I found out what the problem was. The metal spring on the outside of the calipers was re-installed incorrectly and the pads were not align properly as a result. I took them off and re-installed the correct way and I believe the problem is now solved.

Thanks for responding. I appreciate it.

Mark
 

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I suggest you flush all the old fluid out of the system ASAP, this should be done at least once every 2 years anyway.
 

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I do, regular as clockwork. Given what's happened to people who've skimped on other parts of the recommended maintenance, why tempt fate?
Maybe I'm just a risk taker? I remember flushing brake fluid on one car ever: a Subaru that sat for 4 years ... and really what cane out was good brake fluid and the brakes worked same before and after.

I have no plans to flush the Passat anytime soon.
 

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Maybe I'm just a risk taker? I remember flushing brake fluid on one car ever: a Subaru that sat for 4 years ... and really what cane out was good brake fluid and the brakes worked same before and after.

I have no plans to flush the Passat anytime soon.
It is not only your life you are playing with.
 

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While YOU have never had an issue with old brake fluid, that doesn't mean that something can't happen. It's hygroscopic. Over time, it will build up moisture.

It's always a good idea to do it.

Here's a good article on the topic. Why Change Brake Fluid


<checks your location> Good, we're far enough away from each other that I don't have to personally worry about your car's ability to stop properly.
 

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Please enlighten me as to how not flushing your brake fluid is going to kill someone? I'd love to hear it.
Just in case you are unwilling to go to the link provided by VAGguy.


DOT 4 fluid, which has a higher minimum boiling temperature requirement (446 degrees F dry and 311 degrees wet) soaks up moisture at a slower rate but suffers an even sharper drop in boiling temperature as moisture accumulates. Three percent water will lower the boiling point as much as 50%!

Considering the fact that today's front-wheel drive brake systems with semi-metallic linings run significantly hotter than their rear-wheel drive counterparts, high brake temperatures require fluid that can take the heat. But as we said earlier, the brake fluid in many of today's vehicles cannot because it is old and full of moisture.

Water contamination increases the danger of brake failure because vapor pockets can form if the fluid gets too hot. Vapor displaces fluid and is compressible, so when the brakes are applied the pedal may go all the way to the floor without applying the brakes!

In addition to the safety issue, water-laden brake fluid promotes corrosion and pitting in caliper pistons and bores, wheel cylinders, master cylinders, steel brake lines and ABS modulators.
FLUID RELATED BRAKE FAILURES

From time to time we hear about reports of "unexplained" brake failures that caused accidents. When the vehicle's brakes are inspected, no apparent mechanical fault can be found. The fluid level is normal, the linings are within specifications, the hydraulics appear to be working normally and the pedal feels firm. Yet the brakes failed. Why? Because something made the brakes hot, which in turn overheated the fluid causing it to boil. The underlying cause often turns out to be a dragging rear parking brake that does not release. But that's another story.

The same kind of sudden brake failure due to fluid boil may occur in any driving situation that puts undue stress on the brakes: a sudden panic stop followed by another, mountain driving, towing a trailer, hard driving, etc.

A case in point: A child was killed in an accident when the five-year old minivan with 79,000 miles on it his parents were driving suffered loss of pedal and crashed while the family was driving in the mountains of Washington state. Fluid boil was blamed as the cause of the accident.
 

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If you boil even "wet" DOT4 fluid in regular daily driving, you need to first evaluate the way you drive and then everything else.
 

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I would have replied, but others have done a good job of that. Unfortunately it appears that you don't have the capacity to understand.
 
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