clubby

I have just fitted Brembo 4 pot calipers, bigger discs, braided hoses complete with Pagid pads to my 97 Catalunya and also Dot 5.1 brake fluid. Brakes are better than the space shuttle has now.
Now the ABS kicks in if you pull up gently with mild braking. Doesnt kick in if you brake sharply to a halt though.
Anyone got any theories, I have unbolted the drivers side sensor temporarily and problem has gone, although the ABS warning light is now on.
Help!

Pete Croney

If the abs triggers under mild braking, its a wheel sensor problem.

A Select Monitor will diagnose which wheel it is.

Who supplied and fitted the brakes?

Hoppy

Clubby, no answers m8, but fitting new brakes should have absolutely no effect on the correct operation of your ABS.

Is it possible that something has been damaged on the brake back-plate during fitting? Whatever, disconnecting things won't fix it (though might help isolate the cause, of course).

But you've got a problem for sure. Best get it fixed quick. Is that ScoobySport kit? Give 'em a ring anyway.

Good luck. Must be a right bummer to have that happen when you've just fitted those sublime stoppers and want to give the discs a real good hug Stay safe.

Richard.

PS Does the space shuttle have good brakes

Edited to add, Pete Croney - faster than a speeding bullet. Cue Lone Ranger music...

[This message has been edited by Hoppy (edited 27 September 2001).]

DavidLewis

I've experienced this a couple of times recently, especially if braking as you negotiate speed bumps. Its not frequent (though once I nearly drove into the back of the car infront) but I'd love to know the outcome of your enquiries.

clubby

The brakes were originally supplied by Scoobysport for someone with a P1, who apprently preferred the original brakes! My mate got them from a Subaru dealer somewhere near Glasgow for me.

I fitted them myself. cannot see any damage to the now cleaned sensor other than the little metal spindle appears slightly bent.

clubby

I think the ABS sensor is faulty, either that or the backing plate is twisted, and that has in turn bent the spindle on the sensor.

Will know tomorrow for sure, as the car is booked in to fix the problem. I will post a message on here saying what they find.

Pete Croney

If the sensor probe is bent, it will not read the wheel speed and will trigger the abs under braking.

clubby

The probe is only very slightly bent, which may have happened we removed the backing/protective plate from behind the old discs. The plate was too small in diameter for the bigger discs, and had to be removed. It took some grief to get it off, and I think that is where we damaged the probe or damaged the toothed wheel which the probe interfaces with, and that in turn damaged the probe therafter.

Is the probe meant to be touching the toothed wheel? I dont actually understand how the system figures out the wheel has locked, and intermttently releases the pads. I think the that under braking the probe must see that wheel moving, otherwise you are skidding and the pads are somehow released. Do you know exactly how it works?

Pete Croney

The probe sits approx 2mm away from the tone ring. It measures wheel speed by counting the teeth passing the end.

If it is too far away, it can't count the teeth.

You must remove the sensors before attempting to remove the backing plates.

DavidLewis

Good point Pete, since my sensors have bent before, I'll check them over the weekend.