Bora TDI ABS bother

[DIYspanner]

Driving back home, got within 200 yards of the house and a growl started on front O/S and then the ABS came on and the triangle so.

Took the wheel of and I found a small chunk of metal in the knuckle behind the ABS ring. Its slightly bent the ring which I've straightened but no breaks in it.

Wheels of the deck, in first gear, ran the front wheels and although the triangle light is out, the ABS is still on.

How do I cancel the ABS?

 

[Burnerman]

Take the car for a test drive above 20 mph and see what happens......or have you done so already?
John

 

[DIYspanner]

Thanks John!

The ABS light cancelled off before I got 50 yards and stayed off.

Only hiccup is when pulling to a stop there's a slight ABS action. The light is cancelling each time I start the engine. Perhaps the ring needs to be a bit straight in one or two spots.

 

[Burnerman]

Good oh! I have seen this before.
This piece of metal......what do you think it was?
John

 

[DIYspanner]

A bit of rusted nail or bolt perhaps but I'm not going back into the bin to find and photo it. I'm guessing it got picked up in the thread then flung out, hit the inner wing and pinballed down on the the knuckle. Merely speculation though!

I'm just delighted the ABS ring wasn't torn.

 

[DIYspanner]

Will test drive in the morning again the hand back to its owner. That's the bother of online buying of parts, the delay. Had to send two back and buy locally.

 

[DIYspanner]

Still slight intermittent ABS activation just as the car comes to stop. I'm wondering is that more likely the ring or the sensor?

What size should the gap be between sensor and ring on the VW Bora?

If its the ring to replace, with caliper, disc and hub nut removed, the wheel hub should slide hammer out of the bearing inner.

 

[Burnerman]

Only a guess but as the ring was initially damaged it must have touched the sensor so I'd replace that I think....not too expensive but they can be a pig to shift.
No idea what the gap is, sorry!
John

 

[DIYspanner]

I presume the ABS sensor can incur certain damage without the ABS fault warning flagging it up.

It'd be nice if it was the sensor. The likes of Febi make them so should be decent quality.

 

[DIYspanner]

Fitted an Apec brand sensor but occasional ABS activation persists albeit less than it was. The Bora went in for a diagnostics at a garage we know and trust. No fault diagnoses and the fella reckons the ring gap is adequate. Did an 8 mile run with it and no ABS warning. No grounds for an MOT failure since there's no fault so see how it behaves.

 

[Keithmac]

I normally look for 0.5mm air gap on sensors (crank/ wheel speed etc).