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N8Cas
11-18-2009, 03:54 AM
1997 a4 b5 1.8t FWD 5spd 120k mileage 16x7 BBS wheels.

Just installed new front rotors ECS Big Brake OEM (http://www.ecstuning.com/Audi-B5_A4-FWD-1.8T/Braking/Big_Brake_OEM/ES89/), new Stainless steel lines (front only) new hawk hps front pads and OEM rear rotors and mintex rear pads. Here is my problem:

- Still have a low pedal (I bled the brakes twice)

- my biggest concern is the hard knocking that feels like it's coming from the front passenger side. The knocking comes on when I moderately apply the brakes from 30 mph and above. The knocking is fast when going fast and slows when I come to a stop. The knocking gets progressively worse as I continue to drive. I took both front wheels off and took a closer look at the rotors & pads (took those off and looked at both sides of the rotor and the pads); everything looks fine [confused].

- After doing this last night and driving home, I heard the computer or ABS (not sure) making some noise after coming to a stop and taking my foot off the brake and letting it idle. I can not describe it, but it sounded to me like the computer or ABS system was resetting or noticing a problem. The ABS light and BRAKE light came on later when I was on the highway. [confused]


I think I can figure out how to bleed the brakes properly after doing some more research, but this hard knocking is NOT good for the car that I HAVE to drive to get to work today. My wheels are BBS 16x7, so they should be clearing the larger discs I put on up front - I see no heavy wear marks up front. The calipers are not seizing. I did not inspect the backs besides bleeding them without removing the wheels. I'm clueless and need some help!

- is it an ABS problem?
- is it something in back (maybe I screwed up the bearings) even though it sounds like it is coming from up front?

Sorry for such a long post, but I have gotten a lot of good advice from here during the DIY process and I'm hoping someone might be able to help me with these problems. Thanks.

Deep6ed
11-18-2009, 04:52 AM
Squishy pedal usually is one or both of 2 things:

Air in your brake lines (solved by proper bleeding)
Fatigue of your old plastic brake lines. (upgrade time)

Your old plastic brake lines will actually loose their rigidity over time and fatigue and stretch. This causes the pressure caused by braking to force the fluid which would normally go into your caliper for braking into expansion in the lines. This causes the spongy feel because you have to move the pedal further to get the fluid into the calipers to slow you down.

I read that you got SS lines for the front. Thats great, but do not put them on until you have SS lines for the rear too. The reason is that the new SS lines will not expand like your old plastic ones did, but your rears will. That creates an unsafe balance which actually increases the risk of your rear lines rupturing causing brake failure. This is very unsafe. The last thing you want to do is think you upgraded, only to blow out your rear line, lose the ability to stop, and slam your baby into something.

If that doesn't help, you can always VAG your abs system to check for errors. IIRC if you can read it, it's usually fine. Good luck!

N8Cas
11-18-2009, 09:44 AM
What do you think is causing the heavy knocking when I apply moderate to heavy pressure on my brakes? The knocking is pretty loud.

flynnr
11-18-2009, 09:51 AM
what rims are you running? its not rubbing is it? there is a black gaurd on the top of the back of the rotor for the front brakes, push on that further in toward the motor, might be whats grabbing this happened to me

seanj130
11-18-2009, 10:38 AM
make sure that your calliper mounting bolts are tigt, if one is the slightbit loose, it will wiggle out, there fore causing that knocking noise, i had a problem similar to this..

N8Cas
11-18-2009, 11:17 AM
what rims are you running? its not rubbing is it? there is a black gaurd on the top of the back of the rotor for the front brakes, push on that further in toward the motor, might be whats grabbing this happened to me

I have BBS 16x7. I know the guard you are talking about.... It doesn't look like it is touching (but it is awfully close), but I will bend it towards the engine to see if that's the problem - thanks.


make sure that your calliper mounting bolts are tigt, if one is the slightbit loose, it will wiggle out, there fore causing that knocking noise, i had a problem similar to this..

I tightened those suckers real good .... They're tough to get at with a lot of leverage but nothing a good wrench and hammer can't handle.

ECS Tuning-Audi
11-18-2009, 12:55 PM
Did you bleed the farthest (longest - rear pass) brake first? There is an order you must go in to bleed brakes properly.

Also, is your pedal kicking back like the ABS is kicking in?

N8Cas
11-18-2009, 01:07 PM
Did you bleed the farthest (longest - rear pass) brake first? There is an order you must go in to bleed brakes properly.

No. At first, I did not bleed the passenger side back first. I did however, bleed the correct order the second time around. Should I bleed the master cyclinder?



Also, is your pedal kicking back like the ABS is kicking in?

It does, but only when I just start the car or I'm close to idling. Not that often. But the computer noise or clicking (like a bike when you are not pedaling) is still happening when I'm close to idling or slowly rolling. [confused]

ECS Tuning-Audi
11-18-2009, 01:09 PM
It does, but only when I just start the car or I'm close to idling. Not that often. But the computer noise or clicking (like a bike when you are not pedaling) is still happening when I'm close to idling or slowly rolling. [confused]

Oh I see! Hm, could be a funny pressed bearing. The SS lines were cut to fit so those wouldn't be rubbing. How are you dust covers? Did you lube the backs of the pads?

99blueb5
11-18-2009, 01:48 PM
im pretty sure that the clicking noise is the slide pins that need to be greased the caliper wont make full contact and wont slide properly, grease edge of pads and the area where the piston touches the pad

N8Cas
11-18-2009, 02:00 PM
what rims are you running? its not rubbing is it? there is a black gaurd on the top of the back of the rotor for the front brakes, push on that further in toward the motor, might be whats grabbing this happened to me

Hey Flynn,

Did you notice any heavy wear from the dust shield on the rotor? When I took the rotor off I didn't notice any signs of wear


Oh I see! Hm, could be a funny pressed bearing. The SS lines were cut to fit so those wouldn't be rubbing. How are you dust covers? Did you lube the backs of the pads?

Hey Chris, thanks for all the help - I really appreciate it. It might be the dust covers that is hitting it.

I did use anti-squeal on the back of the pads when I set them in.


i'm pretty sure that the clicking noise is the slide pins that need to be greased the caliper wont make full contact and wont slide properly, grease edge of pads and the area where the piston touches the pad

I did notice the slide pins were slightly open and i did NOT grease them. What type of grease should I use?

ECS Tuning-Audi
11-18-2009, 02:17 PM
I did notice the slide pins were slightly open and i did NOT grease them. What type of grease should I use?

There is special caliper grease, for example: Lithium Brake Grease (http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Braking/OEM/ES4812/?salesrep=CArmbruster&utm_source=audizine&utm_medium=forum&utm_content=CArmbruster&utm_campaign=postreply).
http://www.ecstuning.com/product_library/3855/300/VW%20%252F%20Audi%20Lithium%20Lubricating%20Grease .jpg (http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Braking/OEM/ES4812/?salesrep=CArmbruster&utm_source=audizine&utm_medium=forum&utm_content=CArmbruster&utm_campaign=postreply)

N8Cas
11-18-2009, 03:21 PM
Okay I have an update..... I'm leaking something from the back center of the engine block. Talk about a mess, huh. I hope I didn't mess around with the seals for the master cylinder or the master cylinder itself. When I bled the brakes I was pressing hard all the way down to the floor. That's the way my uncle used to do it so that's the way we did it. Not smart on our part. I still have pressure when I pump the breaks though. How do I know if I need a new MC or MC seals?

AudiTechS4
11-18-2009, 03:31 PM
hopefully its just overflow

Nebone
11-18-2009, 03:35 PM
I had a ticking noise when I had drilled rotors installed. Replaced them with plain rotors and it became silent.

Pressing the brake pedal all the way down when bleeding can rapture the seals as during the last 12 years your car was used, the pedal never traveled that far down.

N8Cas
11-18-2009, 08:01 PM
Pressing the brake pedal all the way down when bleeding can rapture the seals as during the last 12 years your car was used, the pedal never traveled that far down.

I'm hoping that the seals were able to take it.



hopefully its just overflow

what's overflow? Another uncle of mine said it might be the valve cover gasket that needs to be replaced. I'll check and see if there is a puddle underneath the car in the morning and see what it is.

I'm going to pull back the dust shields on the front and then grease the slider pins (lithium grease is too damn expensive). Then I'm going to replace the rear mid and rear side lines with SS lines. I hope I can do this underneath my short stands. If that doesn't work, I think I'll have to look at the back wheels, specifically the bearings. Then, a proper bleeding. Am I missing anything?

99blueb5
11-18-2009, 10:36 PM
I'm hoping that the seals were able to take it.




what's overflow? Another uncle of mine said it might be the valve cover gasket that needs to be replaced. I'll check and see if there is a puddle underneath the car in the morning and see what it is.

I'm going to pull back the dust shields on the front and then grease the slider pins (lithium grease is too damn expensive). Then I'm going to replace the rear mid and rear side lines with SS lines. I hope I can do this underneath my short stands. If that doesn't work, I think I'll have to look at the back wheels, specifically the bearings. Then, a proper bleeding. Am I missing anything?


just get some high temp synthetic axle grease or bearing grease, pretty cheap at any auto parts store, wipe the old grease off first

N8Cas
11-20-2009, 03:28 AM
You know what, I remember greasing the slider pins pretty good, somebody mentioned that it could be an off-balanced rotor. Has anyone ever had to deal with that?

flynnr
11-20-2009, 06:31 AM
no i dont remember seeing much of any damage on the dust shield, i only went around the block twice before i went and figured it out though

gli_ryan
11-20-2009, 06:33 AM
make sure your abs sensor is in there good. I think the gap needs to be like 1/32 of an inch between the sensor wheel and the senor itself. So if you have too big of a gap (the sensor not sitting properly) then you could get the abs kicking on.

N8Cas
11-20-2009, 09:50 AM
make sure your abs sensor is in there good. I think the gap needs to be like 1/32 of an inch between the sensor wheel and the senor itself. So if you have too big of a gap (the sensor not sitting properly) then you could get the abs kicking on

I don't even know where the ABS sensor is on the front.... I don't remember messing around with it at all... I'll have to look into that.


Also, if I have SS lines in the front is it ESSENTIAL to get them in the rear as well? B/C that would be an extra hundo plus the hard to get to install of the rear mids. My jack doesn't put the car up that high!!!

ECS Tuning-Audi
11-20-2009, 10:22 AM
The ABS sensor is easy to find. It is the only wire going to the assembly! Since you have a 97 you don't have the pad sensors correct? So the only other wire there goes to the assembly.

As for SS lines, it SHOULD be replaced in the front and rear so extra stress isn't being transferred to the non-ss lines. The SS lines don't flex as much, so the normal rubber lines in the back will. This COULD cause a line blow out. At least put them in the rear as well so that the braking is even on all four corners. The mids shouldn't be an issue nearly as much as the rubber rears, but you should just pony up and do them all.

We sell the rears pretty cheap! click here for ordering information and pricing.
http://www.ecstuning.com/product_library/14697/300/Exact-Fit%20Stainless%20Steel%20Brake%20Lines%20-%20Kit%20.jpg (http://www.ecstuning.com/Audi-B5_A4-Quattro-1.8T/Braking/Lines/?salesrep=CArmbruster&utm_source=audizine&utm_medium=forum&utm_content=CArmbruster&utm_campaign=postreply)

onemoremile
11-20-2009, 10:39 AM
Any knocking sound is something loose. Double check everything including the control arms.

N8Cas
11-20-2009, 11:46 AM
Any knocking sound is something loose. Double check everything including the control arms.

Yeah, I think you're right. It is definitely a knocking and it's one knock per revolution. I thought I tightened everything extra tight. I might need to get the torque wrench and do everything to spec - I wouldn't think anything NOT to spec would cause such a loud knocking though. I didn't even touch the control arms - I'm going to print out this entire thread and make sure to check everything when I work on it this weekend.

Any one ever have an off-balanced rotor?

onemoremile
11-20-2009, 12:02 PM
Get the car on jack stands. Place a jack under the hub and raise it to ride height (when the car starts to pull off the closest stand). Rotate the wheel and listen.