[wrighar]

I see you've done the wheel bearing, that would have been my guess (as the teeth move closer or further away from the sensor and give false pulse readings). Looks like someone has spent a lot of mony trying to fix it.

Do you get any ABS failure lights? or does it think it's working properly.

Do you know which wheel it is 'unlocking'? that would give you a good starting point.

My Aero has done this only once, just as the NSF wheel bearing went, and when turning right.

I have seen 1 saab with the wrong ABS wheel bearing which caused much ABS confusion. One had been replaced and a 80 something toothed wheel had been fitted instead of the 40ish toothed one

Andrew

PS. Welcome to Saabscene. I see you have a 99T too

 

[wrighar]

the NSF wheel bearing nuts are the one that are slightly prone to self loosening.

Check for any signs of rust around the washer behind the nut, and listen for any creaking from that wheel when driving at a crawling pace (as the wheel bearing moves around).

I would be suspicious of the bearing or sensor for that wheel.

Andew