scary high speed moment

[DamoM]

I have had 2 recent scary experiences in my RS2 which have left me very puzzled.

Was travelling on a dual carriageway at a high speed on the n/s lane when suddenly the steering pulled violently to the right and forced me into the other (thankfully empty) lane. At the very moment it did this, the abs light came on. Then for a few seconds (as I coasted off throttle to allow the car to slow) the steering was still pulling to the right and the light remained on. It then extinguished and the pulling ceased at the same time. It was a very scary and dangerous moment.

The next day I took the car to my garage for them to have a look at it and drove slowly there. The problem repeated itself (albeit at a much slower speed) once.

The car is at the garage. They have checked brakes, wheel bearings etc. There is no sign of binding from either and so they are looking at the abs controller now but are scratching their heads.

Any ideas??

[URquattroGus]

Abs wheel sensor signal fault triggering premature abs activation? I think there is also a controller that senses decelleration, could that be at fault.

Slight stabs in the dark, I'm sure someone with more first hadn experience will be along soon...

[avants2turbo]

If your in need of any braking parts after the garage have looked, ive got an abs pump and ecu tht were removed from a fully working s2 avant im only in lingfield in surrey if you want to try them out

[DamoM]

Abs wheel sensor signal fault triggering premature abs activation? I think there is also a controller that senses decelleration, could that be at fault.

Slight stabs in the dark, I'm sure someone with more first hadn experience will be along soon...

They have checked the abs sensor but surely it would only affect it in this way if I was on the brakes at the time? I was accelerating hard!

Never heard of the controller sensing deceleration before. What is the purpose of that?

[DamoM]

If your in need of any braking parts after the garage have looked, ive got an abs pump and ecu tht were removed from a fully working s2 avant im only in lingfield in surrey if you want to try them out

May well take you up on that offer. Are the abs parts the same between RS2 and S2?

[driftin jo]

It could be the CV joint , I once had one do the same as you describe , although it was at much less scary speed, it nearly yanked the steering wheel out of my hand though and I was close to going through a hedge . Try driving the car in a tight circle on full lock in a car park and listen for clicking sounds from the wheels .

[DamoM]

It could be the CV joint , I once had one do the same as you describe , although it was at much less scary speed, it nearly yanked the steering wheel out of my hand though and I was close to going through a hedge . Try driving the car in a tight circle on full lock in a car park and listen for clicking sounds from the wheels .

Thanks Jo, I'll get the garage to try that.

[WabTheKing]

i had this on my dads allroad where the esp would kick in whilst driving in a straight line around and above 100mph, very un nerving!!!!! unfourtunatly he had already seen his ar53 with the car and sold before i had chance to get to the bottom of it. If you can run vagcom from inside the car while driving get someone to look at the output speeds of the sensors or datalog and try and make the fault reocur,

my gut feeling would be the control unit going faulty energizing the solenoids in the valve body if there are no errors stored/wheel sensors check out ok and no mechanical problems present

[driftin jo]

The car I was in didn't have ABS as it was an old golf and I was just thinking how the light could have come on at the same time in your case. It seems to me that if the CV was the cause then the force on the joint could pull the ABS ring teeth away from the sensor wile this was happening as the teeth are part of the CV joint and the stress would be enough to deflect the shaft and thus the ABS teeth on the joint causing the light to come on because of lack of signal.

[WabTheKing]

oooo thinking along your lines jo, had a loose abs pickup ring cause weird problems too, so maybe pick up teeth are rusty/ corroided?? a locking cv joint is a very scary thought

[DamoM]

oooo thinking along your lines jo, had a loose abs pickup ring cause weird problems too, so maybe pick up teeth are rusty/ corroided?? a locking cv joint is a very scary thought

@Wab and Jo. Yes it sounds plausible. They abs sensors and ring have been inspected and look ok but if they were getting deflected they this wouldn't be detectable on inspection.

The only thing was that I was travelling in a completely straight line and so I would have thought that the chances of the cv joint locking was remote?

[WabTheKing]

pull the abs unit plug and drive again, this should iliminate any abs influance leaving only the drive train to monitor

[driftin jo]

@Wab and Jo. Yes it sounds plausible. They abs sensors and ring have been inspected and look ok but if they were getting deflected they this wouldn't be detectable on inspection.

The only thing was that I was travelling in a completely straight line and so I would have thought that the chances of the cv joint locking was remote?

I was also travelling in a straight line in the golf when it tried to put me through a hedge , without any warning it just pulled the wheel to the left, after that a few miles on the steering would now and then give a little twitch like it was going to do it again.
I drove it home slowly and when I tried to reverse it up my drive the CV joint spat it's balls out.

[WabTheKing]

I was also travelling in a straight line in the golf when it tried to put me through a hedge , without any warning it just pulled the wheel to the left, after that a few miles on the steering would now and then give a little twitch like it was going to do it again.
I drove it home slowly and when I tried to reverse it up my drive the CV joint spat it's balls out.

did this have a split cv boot or anything? clicking on turns? or completly unprovoked?

[prj]

The reason the ABS warning light came on, is because your wheel seized and now the speed reading from that wheel was lower than from all the other wheels.
Very simple. Try lifting your car up and then just accelerating while it's lifted in the air.
You will get the same error in ABS, because not all wheels will move exactly at the same rate.

Check indeed for a mechanical problem. The bearings, the diff etc...
I am very sure it's not the ABS or the ABS ecu doing that. Kind of puzzled as well, why people try to blame everything on electronics, when this very, very clearly sounds like a mechanical issue.