Braking twitching - Why????

[merc180k]

Hi,

I bought my car about 1.5k miles ago and at point of sale the car had new pads all round, new shoes, new rear discs and new tyres for 3 wheels.

All was perfect, (aside from a small adjustment for the handbrake done after a month) but now under braking there seems to be a wobble/twitching of the pedal and I can feel it through the wheel.

Anyone have any idea what could be the possible cause or what I can check to diagnose the problem?

Thanks

Simon

 

[television]

This would be warped disc on the front.

 

[grober]

If its not a warped disc like Malcolm suggests then is it possible that with the weather getting worse rain etc and road surfaces slippery that you are just feeling the ABS thro the pedal?

 

[kth286]

Start by checking that the wheel bolts really are tight.

When technicians are under time pressure all sorts of things get missed.

 

[television]

Doing some more studying of ABS there are some faults listed where the pedal can pulse lightly, often caused by low voltage to the ABS pump

 

[merc180k]

It's not the ABS through the pedal as it's more like I'm feeling a vibration from the wheels after having done another 50 miles today.

How can you check for a warped disc - is it visible to the eye while on the car? They look ok to me but I'm no mechanic! What actually causes it and what will happen if I don't replace the discs?

 

[television]

It's not the ABS through the pedal as it's more like I'm feeling a vibration from the wheels after having done another 50 miles today.

How can you check for a warped disc - is it visible to the eye while on the car? They look ok to me but I'm no mechanic! What actually causes it and what will happen if I don't replace the discs?

Only with a dial gauge, also one with a hook to get to the rear of the disc as the back plate is in the way.
By jacking and spinning each front wheel in turn you could possibly feel the wheel in question

 

[merc180k]

An update for all you helpful folk.

Took the car to a nice branch of Farmers Autocare and they rebalanced the 2 front wheels as a starter for 10 (and for free too). The wobble is almost completely gone when driving and completely gone under braking. All good as it probably saved me a small fortune.

Thanks for all the input though.

Simon