Something feels off

Flanders

Flanders

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It's just started. Either that or it's come on really slowly and I haven't noticed 'til now.

When I brake I'm getting a strange sensation through the pedal and steering. The brake pedal seems to have a fine degree of freeplay and then it sort of "catches". This isn't what's really bugging me though. The problem is that when this "catching" occurs, the steering responds by giving a twitch. It almost feels like my left and right front brakes are slightly out of time resulting in an imbalance of sorts. The sensation is dampened the slower I'm going and the brakes feel smooth at low speed.

I haven't needed to change brake pads on this car yet and there is no grinding but could it be that my pads are worn? My only other thought is that the front tyre pressures are not equal, causing a different amount of friction with the road on either side of the car.

Just got back from a meeting so I haven't had time to check it out but on the drive I noticed this and I get a worried feeling inside when this sort of thing happens. In other words I do a forehead slap and I see $$$ signs.
 
N

Nocturnity

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Could be your brake pads wearing unevenly. Perhaps a cracked disc. Not quite sure but it shouldn't be too expensive to fix.
 
W

W@P

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Could be that one of the discs are bent and when you brake the one side brakes more when it catches the bent part.
 
Flanders

Flanders

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4

4cer

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well if im braking on a corner from around 120 - 0 i get this sensation if that helps.

/puts on flame suit

and volkswagens are crap so you will probably get it from around 40Km/h :p
 
Flanders

Flanders

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Eish, I dunno. Looks like I'll have to take it in. I just hate that because these guys will take you for a ride if you seem even slightly clueless.

Re. that point on a warped disc - would you not feel a sort of oscillation/vibration through the steering if you have a warped disc as the uneven disc is revolving between the caliper and pads?

Anyway, my tyre pressure theory is out the window. Checked and normal.

Upon further investigation I can sum it up as this: when I apply slight braking or even slight acceleration I get a sensation through the steering. The steering gives a small "twitch" to the right upon either throttle or brakes. (and no, it's not the TDi's torque steer) :p
 
C

CaTcH21

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Wait a sec, if it happends when accelerating, there is no way it can have anything to do with your braking system. The problem lies somewhere in your suspension. Start with the shocks ...
 
F

Frankie

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Flanders said:
It's just started. Either that or it's come on really slowly and I haven't noticed 'til now.

When I brake I'm getting a strange sensation through the pedal and steering. The brake pedal seems to have a fine degree of freeplay and then it sort of "catches". This isn't what's really bugging me though. The problem is that when this "catching" occurs, the steering responds by giving a twitch. It almost feels like my left and right front brakes are slightly out of time resulting in an imbalance of sorts. The sensation is dampened the slower I'm going and the brakes feel smooth at low speed.

I haven't needed to change brake pads on this car yet and there is no grinding but could it be that my pads are worn? My only other thought is that the front tyre pressures are not equal, causing a different amount of friction with the road on either side of the car.

Just got back from a meeting so I haven't had time to check it out but on the drive I noticed this and I get a worried feeling inside when this sort of thing happens. In other words I do a forehead slap and I see $$$ signs.
Click to expand...

I'd going along with the suggestion that your brake disks are warped, which can explain the excessive free play before getting braking effect and the strange twitching of the steering.
It's likely that only one of the brake rotors (disks) is warped.

When the brake rotors warp they displace the brake pads back into the callipers due to the rotor axial run-out and then when the brakes are applied the pads need to advance further than normal to grip the rotors.

When accelerating from a standstill or after braking while cruising, the warped rotors will once again displace the pads into the callipers, which will most likely cause the twitch at that time.

The brake rotors are subjected to extreme thermal cycling, and any impurity in the casting will cause them to warp.
 
Last edited:
F

Frankie

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Flanders said:
Re. that point on a warped disc - would you not feel a sort of oscillation/vibration through the steering if you have a warped disc as the uneven disc is revolving between the caliper and pads?
Click to expand...
Yes you will feel the oscillation until the pads are retracted into the callipers.
 
SlinkyMike

SlinkyMike

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Skim discs or wheel alignment but don't take a bunch of punters advice about your brakes dude - head to your mechanic pronto!
 
Pitbull

Pitbull

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Flanders said:
Eish, I dunno. Looks like I'll have to take it in. I just hate that because these guys will take you for a ride if you seem even slightly clueless.

Re. that point on a warped disc - would you not feel a sort of oscillation/vibration through the steering if you have a warped disc as the uneven disc is revolving between the caliper and pads?

Anyway, my tyre pressure theory is out the window. Checked and normal.

Upon further investigation I can sum it up as this: when I apply slight braking or even slight acceleration I get a sensation through the steering. The steering gives a small "twitch" to the right upon either throttle or brakes. (and no, it's not the TDi's torque steer) :p
Click to expand...

This was the reason I asked if it does the same if you change gears.

If you push in the clutch the torque is off the motor then the car will make a jurk to one side and when you release the clutch it will jurk again in the opposite direction. If this is the case you need to replace the engine mountings (If your driving a diesel there is a big chance that they are worn due to the torque) and also the ball joins on the lower control arms of the steering.

It's not a need to do now kind of thing but it will get worse to such an extent that you can no longer control the car when increasing or decreasing speed ;)
 
W

W@P

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This is whats happening when you apply the brakes.

1fire.jpg
 
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