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Discussion Starter #1

The car makes strange noises while braking. Kind of a repeating Ua-Ua-Ua-Ua like sound.

The car had previously failed to pass motor vehicle inspection (loose spindle joint) and was turned over to a mechanic for repairs. The car was picked up from the mechanic two days ago and afterwards had this problem. The car passed vehicle inspection roughly an hour before this video was recorded. They did not find any faults with the vehicle and it was approved for use on public roads.

What is this noise? How can I fix it?
 

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Couple things, first I would take it back to the mechanic and explain, noise AFTER they worked on it. If it only as you describe happens upon braking,does the noise seem to be coming from the same side as the repair ?, I have to think so. A couple of things come to mind that are easy to fix/diagnose; one, is that during repairs it is easy to bend the brake "backing plate/dust shield) as it only is a few mm away from rotor,and then is rubbing against rotor. However this is usually a continuous "rub" , the second is the rotor , wheel or both have debris between their mating surfaces,so the rotor is "wobbling", and the third is that upon disassembly and reassembly something was left loose, possibly a tie rod end.
 

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Discussion Starter #3
Thank you for your reply!

I'm not sure where the noise comes from because I have to be driving the car and therefore can't walk around the vehicle listening to different parts to locate the origin. I've phoned the mechanic and he doesn't have a clue what it could be. Kinda frustrating that. :/
 

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if the mechanic is responsible enough to take your money,he should be responsible enough to take a ride/listen. O.K. you can try this......in an open parking lot, drive and turn the wheel as much as possible while braking and see if turning car to left or right makes a difference.
 

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You can try driving next to a wall to see if the noise is louder on one side or the other.
 

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Discussion Starter #6
I've been trying to pay attention while driving and I think it is coming from the right front wheel. I'll try to find an empty parking lot somewhere and take off the wheel and take a look. Perhaps the problem will be obvious enough for me to tell?
 

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1st I would check for play in the wheel. I suspect a wheel bearing, but it could be tire cupping as well. Hard to tell by sound over the internet.
 

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Discussion Starter #8
1st I would check for play in the wheel. I suspect a wheel bearing, but it could be tire cupping as well. Hard to tell by sound over the internet.
If it was the wheel bearing or tire cupping shouldn't the noise be present all the time? And not just when braking? I imagine that when driving at 120 km/h on the highway something like that would result in noticeable noise and vibration - which is not present in this case.

Instead, the noise is only present when lightly applying the brake such as when slowing down at a red light. If I press down hard on the pedal, the noise goes away, but driving like that isn't always possible because of needing to adapt to other traffic and it also makes for an unpleasant driving experience in general.
 

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"the mechanic fixed the loose spindle joint" could you describe or tell me/us what the part was ? and what side was it on ? It definitely sounds like rotor is not running true and or caliper bolts might have been forgotten to be tightened, since this happened right after/immediately after you had work done..... and more probable if noise can be confirmed coming from same side as work was done on.
 

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Discussion Starter #10


I wasn't there when the mechanic fixed the car so I don't know exactly what he did. I do have the problem listed in the motor vehicle inspection sheet:

SPINDELLED (5.3.4) FRAM HÖGER ÖVRE, FRÄMRE GLAPP
SPINDELLED (5.3.4) FRAM VÄNSTER ÖVRE, FRÄMRE GLAPP

Based on this it affected both front right and left wheels. I took a look today and those arms above the wheels (pictured above) are very shiny compared to the rest.
 

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thanks for pic, he replaced the top two control arms......if possible/able, remove wheel and check to see if brake backing plate/dust shield is touching or near rotor, while wheel is off clean inside of wheel where it makes contact with rotor. Not knowing how he removed bolt (shown in picture holding control arms in place, now a new bolt) he might have taken the strut out, usually that bolt is a pain to remove but it appears relatively rust free so maybe he was able to get bolt out easily, check the dust shield first.
 

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were both sides done ? ,I see two parts listed ,but each side has two parts, a front and a back control arm, if only one side was done,and the noise is coming from the side the work was done on (in pic appears to be passenger side) then I suspect the dust shield as mentioned.
 

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Discussion Starter #13
Yes, both sides of the car were done (front right wheel and front left wheel).

I went with my father today and we took off the wheel and tried to have a look. Unfortunately, nothing seemed obviously wrong. The dust shield had plenty of clearance. My father also tried whacking the break with a hammer a few times and adding some oil. Apparently this can help sometimes. It didn't in this case.

I also took some pictures. They are behind the spoiler tag below.







 

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1st I would check for play in the wheel. I suspect a wheel bearing, but it could be tire cupping as well. Hard to tell by sound over the internet.
x 2 on the wheel bearing. I like the ATE rotors.
 

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.
 

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They're ATE "PowerDisc" rotors. One of the functions of the groves is to serve as wear indicators. From the corrosion present I would say they've been on the car a while.
 

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Discussion Starter #17
The rotors are not original. I can't remember exactly when they were replaced but it's been a couple of years now. There was no real reason why. The old ones worked fine. My father is just big on preventive maintenance. So he went and got these from Germany. They are supposed to be high quality.
 

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Assume he oiled the caliper pins which might do the trick as it appears that the 'boots" have worn out and a pin(s) might be holding the rotor from floating to a neutral position after the brakes have been applied. Hopefully that does the trick. Thanks for pics.
 

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Yes, both sides of the car were done (front right wheel and front left wheel).

I went with my father today and we took off the wheel and tried to have a look. Unfortunately, nothing seemed obviously wrong. The dust shield had plenty of clearance. My father also tried whacking the break with a hammer a few times and adding some oil. Apparently this can help sometimes. It didn't in this case.

I also took some pictures. They are behind the spoiler tag below.







Taking a look at the 4th picture, it appears there's excessive wear on the outer edge of your rotor, which isn't typical. Not sure if it's the root cause of the problem because you've had these rotors for a while and the noise began only after the mechanic replaced the upper control arms, but I would start there. Also, you can see a deep groove (not referring to the power disc grooves) near the outer edge of the rotor. If it's deep enough, it could cause erratic braking issues, not to mention, the fact that you had bad upper control arms/bushings could create braking issues over time. You may want to check to see if the rotors are warped because this too can cause braking issues, especially if pads are not seated problem. Do you feel any vibrations in the brake pedal or steering wheel when applying the brakes? If so, this may indicate a bad/warped rotor. Also, it's difficult to tell from your last picture how thick your inner brake pad is, but it looks very thin. Nevertheless, I suspect there's some grinding causing the noise, which is clearly more audible when you're coming to a stop. Finally, replacing the upper control arms involves removing the pinch bolt and the other end of the control arm without removing anything else besides the wheel, unless the mechanic opted to remove the strut to set the proper angle of the control arms which cannot be torqued inside the car. If you happen to still have your old rotors, I would reinstall them to see if the noise goes away or take it to your mechanic and have him inspect the brakes. Best of luck!
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the bolts/nuts for the strut and bolts for the caliper appear still covered in grim so doubt if strut was removed. The boots for the caliper pins are shot (should not see the shiny part of the pin in pic #6 (last pic) so caliper might no longer be "floating" which would explain pads (inner and out) different thickness appearance. The noise is harmonic/has a frequency of once every revolution of the wheel. This indicates to me, that as you apply brake lightly, caliper is closing but rotor is not running true, either warped which I doubt,since it would have been noticeable BEFORE you had the work done, or the surface between the inside of rotor where it mounts to axle hub had crap dislodged when repaired and now the mating surfaces are compromised not surface to surface......a piece of material .25 mm in thickness translates to 1mm at the perimeter of the rotor as runout. Suggest caliper removed, rotor removed, inside and outside mating surfaces cleaned as well as face of axle hub and inside surface of the allow wheel rim. An other possible indication of this (rotor runout ) is high speed vibration caused by the caliper being forced back and forth each time the wheel makes one revolution. Approximately 14 pulses per second, 860 pulses per minute going 100km per hour.
 
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