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Discussion Starter · #1 ·
My 2003 Passat had a soft pedal after I did the brakes all wheels. I didn't like it so I thought I would try bleeding. I started rear pass. then rear drivers, and front pass. then front drivers. I used the motive bleeder, and bleeding went ok I thought no air at each wheel. I put plenty of fluid in the Motive and the master cylinder. I'm having a hard time seeing the level in the master the plastic is so yellow. I noticed when using the Motive bleeder it had a lot of air in the clear hose. So my thought is maybe I ran the master dry. Don't know can't look in it some kind of check valve in the top. Any help I sure need it. THX David
 

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The fact that the soft pedal started right after the pad change, should be the primary focus of your problem solving. Just changing the pads should not have introduced any air in the system, since you are not opening the system.

Did you happen to open the bleeders when you changed the pads? That may have introduced the air and you need to try bleeding again.

If not, some have resolved this problem by cycling the ABS system, either by using VCDS software or hard braking on gravel to activate it. Sometimes this works on it's own, other times you need to bleed again after the ABS cycling.
 

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One thing I would suspect is the if you changed out the rear pads.
When changing pads on the rear you must turn the pistons back into the caliper so the new pads fit. By any chance did you turn the wrong way at first then go back the other way.
If you turn the piston the wrong way to far, air will get into the caliper and cause the same symptom.

I'll admit I've done that myself.
I changed out the rear pads on my 1998 GLS and the I couldn't get the piston to turn so I went the opposite way. I actually turned it out to far and part of the seal came of the piston. After that a proper bleed was in order.
 

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Discussion Starter · #4 ·
Thank you, there's a little more to my problem. It's been quite some time since I did the job don't recall opening the bleeders. After the brake job the spongy pedal I took the car to a mechanic to bleed them he test drove the car he claims and the brakes are fine. They were not ok. So I parked it over a year now getting back to it. I'll try bleeding again as soon as I settle down. I need to be able to see the fluid level. Does that screen pull out. If not I will have to change the revivor. Thx
 

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I'd start by changing the reservoir, not that it will fix the problem, but makes checking fluid level easy.

Another story, only a little relevant though: I've got a 1986 Mercedes 560SL roadster, and bled the brakes in the usual way, although using the brake pedal for pressure, and with a one-way check valve at the bleeder screws. I watched the reservoir and topped-up as needed, but the thing began to purge air from the rear calipers, and the brake pedal was soft. It turned out that I had run the rear-brake section of the reservoir dry, because the design of the reservoir prevents you from noticing that. Here was the weird thing; to fill the rear section of the reservoir, you first have to fill brake fluid until it is almost to the rim of the threaded opening.
 

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Thank you, there's a little more to my problem. It's been quite some time since I did the job don't recall opening the bleeders. After the brake job the spongy pedal I took the car to a mechanic to bleed them he test drove the car he claims and the brakes are fine. They were not ok. So I parked it over a year now getting back to it. I'll try bleeding again as soon as I settle down. I need to be able to see the fluid level. Does that screen pull out. If not I will have to change the revivor. Thx
Got it.
The screen can be removed from the reservoir, but if it's original it might want to break on you. I would recommend replacing the reservoir.
From there you can flush the entire system. Which I would highly recommend after letting this sit for a year. Only because if there is any air in the system, moisture will enter and we all know moisture in the braking system is a no no. Best to just have it all flushed out.
 

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Discussion Starter · #7 ·
Got it.
The screen can be removed from the reservoir, but if it's original it might want to break on you. I would recommend replacing the reservoir.
From there you can flush the entire system. Which I would highly recommend after letting this sit for a year. Only because if there is any air in the system, moisture will enter and we all know moisture in the braking system is a no no. Best to just have it all flushed out.
Got it.
The screen can be removed from the reservoir, but if it's original it might want to break on you. I would recommend replacing the reservoir.
From there you can flush the entire system. Which I would highly recommend after letting this sit for a year. Only because if there is any air in the system, moisture will enter and we all know moisture in the braking system is a no no. Best to just have it all flushed out.
Great idea I will replace the reservoir. I've been looking not cheap any ideas. After I will flush. Don't know how but always have Utube. Thx
 

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Yeah unfortunately those reservoirs aren't cheap. I'll offer up my .02 cents worth.
I tried going cheap a few years ago when I replaced the reservoir on my 1998 GLS. It lasted less than a year. Now admittingly that was down here in the harsh Phoenix summer climate.
It was the Febi brand and the plastic got so brittle it just started cracking and leaking fluid. If you can swing it, go Genuine. The type of plastic being used is noticeably different (better quality) than the cheapo ones.

Side note:
If you've got a manual transmission, when swapping out the reservoir, don't forget to snip off the very end of the nipple that goes to the clutch master cylinder. That's a mishap known to happen around here.
 

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Discussion Starter · #9 ·
Yeah unfortunately those reservoirs aren't cheap. I'll offer up my .02 cents worth.
I tried going cheap a few years ago when I replaced the reservoir on my 1998 GLS. It lasted less than a year. Now admittingly that was down here in the harsh Phoenix summer climate.
It was the Febi brand and the plastic got so brittle it just started cracking and leaking fluid. If you can swing it, go Genuine. The type of plastic being used is noticeably different (better quality) than the cheapo ones.

Side note:
If you've got a manual transmission, when swapping out the reservoir, don't forget to snip off the very end of the nipple that goes to the clutch master cylinder. That's a mishap known to happen around here.
Yes your right I always try to cheap out and pay the price. Mine is a Auto but good info I was wondering what that was for.
 

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Here is a self-proclaimed top-tip: look for used reservoirs off of (somewhat) newer A4’s. I picked up a like new ‘09 master cylinder /reservoir combo for like $30 in great shape. OK, it won’t last 20 years, but I only needed to get another few years out of it.
 
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