OV9

Hi,

This is quite odd, and isn't a judder

But when I brake, the braking seems to ebb and flow a bit - it's very hard to brake smoothly

It's almost like I'm gently modulating the brakes, roughly every second

Any thoughts what that might be? (other than a very crap driver)

ABS fault?

Possibly pad material on the discs? Try some repeated high speed heavy braking to an almost standstill but don't come to a complete stop.

Brake discs have turned into tank tracks?

Leak or sticky seal in your servo? I had really weird brake issues towards the end of our time with Mrs Mik’s KA years ago. Inconsistent braking. Brakes reluctant to release. Pulled off a pipe and sprayed some lube into the servo unit - exercised the pedal a bit - perfect after that.

Or faulty one way valve in the vacuum pipe to the servo.

Mine do it as my rear drums have some roundness issues, do you have drum brakes.

Dave!

John wrote: Mon Mar 21, 2022 6:49 pm Possibly pad material on the discs? Try some repeated high speed heavy braking to an almost standstill but don't come to a complete stop.

Try this first. When i has those shit Pagid RS14's they fouled the discs up something rotten. I cleaned the discs up with an emery wheel on the drill.

Agree with others that it sounds like pad deposits.

It can be hard to shift but my experience tells me to soak the discs in water, put the car away in the garage ( or leave it on the drive, wherever! ) and don’t drive it until you can see visible oxidisation on the discs.

Then drive and apply the brake to try and get the pad to scrub the disc clean.

John wrote: Mon Mar 21, 2022 6:49 pm Possibly pad material on the discs? Try some repeated high speed heavy braking to an almost standstill but don't come to a complete stop.

My bmws all did this after heavy braking. Good tip.

Thanks for all the tips and suggestions

I'll head out at night when the roads are clear and try some back to back high speed (almost) stops

We have some dual carriageway near the house which will be fine for this

@DaveE if it is this, you want to do 6-8 stops in succession from around 70 to walking pace, about 80% of max braking level (so you ensure ABS doesn’t get triggered). Want them nice and hot - likely to be smelly.

mik wrote: Fri Mar 25, 2022 9:52 am @DaveE if it is this, you want to do 6-8 stops in succession from around 70 to walking pace, about 80% of max braking level (so you ensure ABS doesn’t get triggered). Want them nice and hot - likely to be smelly.

Thank you...

I've just been reading up on this

Do not come to a complete stop, and give them a good cool down afterwards

Sounds like fun