CV joint ?

[peter306]

Hello all, again.
Driving along in a straight line, tapping noise started from the front left, slowed down, noise slowed down, sped up, noise sped up, then the ABS light came on, would that be the cv joint as it would rotate at a different speed if it was slipping
Rgds Peter

[moizeau]

Have you done the car park check? Full circle LH then RH, that should show a CV, if not look further

[Doo]

Hello all, again.
Driving along in a straight line, tapping noise started from the front left, slowed down, noise slowed down, sped up, noise sped up, then the ABS light came on, would that be the cv joint as it would rotate at a different speed if it was slipping
Rgds Peter

A faulty CV joint wouldn't normally cause an ABS issue. However, if the nut holding the driveshaft has broken or fallen off, the CV could start walloping around. But I suspect you would be very aware of that scenario. I think perhaps your wheel bearing may be done as that would make a speed related noise and it would open up the air gap between the sensor and the bearing mounted reluctor ring.

Jack up the affected wheel and try to move it by placing a hand on the bottom (6 o'clock) and the top (12 o'clock) of the tyre. Any movement suggests it is time to take it (slowly) to the nearest garage with a bearing press....

[MattBLancs]

I would suspect an ABS ring has fractured. CV joint gets rusty, rust occupies larger volume than steel. Corrosion builds under CV joint reluctor ring until one day it snaps. Sometimes ring will then hit ABS sensor other times just the increased gap is enough for ABS system to throw a wobbly.

Can buy new ABS reluctor rings (need to measure the inside diameter and number of ridges round the perimeter) or buy a full CV joint complete with the ring.


I'd have thought loose driveshaft nut very unlikely - and you'd have massive wheel bearing play as a more obvious symptom

Matt

[Hell Razor5543]

I would also agree that the reluctor ring is likely to have failed. I had this happen on my second Xantia. I got a pair of rings from ebay, and the process of replacing them did not take too long. I would check the reluctor rings on both drive shafts, as if one has failed the other is probably not far behind.

Reluctor rings are not that expensive. This is an example (but may not be the right ones for YOUR Xantia);

https://www.ebay.co.uk/itm/144541226371 ... BM5qjGh-Zg

[peter306]

Hello all again, bearing in mind this is a 22 year old Xantia 1.8lx, 179K miles, going well.
Checked the reluctor ring, couldn't see anything broken but all it would take is an hairline crack, wasn't in the best of condition though. I've ordered a new cv joint, see what happens.
The nut was fine, no rumbling going round some sharp bends, bearings are good. the tapping noise stayed constant on direction changes, only altered on speed changes.

[Doo]

Hello all again, bearing in mind this is a 22 year old Xantia 1.8lx, 179K miles, going well.
Checked the reluctor ring, couldn't see anything broken but all it would take is an hairline crack, wasn't in the best of condition though. I've ordered a new cv joint, see what happens.
The nut was fine, no rumbling going round some sharp bends, bearings are good. the tapping noise stayed constant on direction changes, only altered on speed changes.

I'm stupid.... I didn't take the age into account I assumed the reluctor ring was built into the bearing like the (pair) I have just replaced in my wife's 2007 C4.

Apologies for the misleading info.... Although, in my experience, worn bearings can affect the ABS function as I stated.

[Hell Razor5543]

Before you replace the CV joint see if you can move either reluctor ring. If it can be moved at all it will need to be replaced. It can be done without removing the driveshaft from the gearbox (although care must be taken, otherwise gearbox oil will leak out), but you do need to get the hub off the driveshaft. IIRC 30 minutes in the oven at around 180C will be enough to expand the new ring enough for it to fit over the CV joint (but make absolutely certain the CV joint is clean and free of rust before trying to fit a replacement ring).

As I said, I have done this before. I took my silver Xantia (Gracie) up to CitrJim as he had done this before, so had a wealth of experience. We did both reluctor rings, to eliminate the probability of the other ring failing not long afterwards.

[peter306]

Hello James, I checked the reluctor ring, couldn't see any obvious damage but did find a couple of tiny shiny marks on a couple of adjoining teeth, as the noise only happens when I get up some speed this would suggest that either the ring or cv casing is distorting under centrifugal force, as I couldn't be sure i've gone for the joint, drive shaft is already off and apart.
Maybe i'm overthinking this but I'd rather go over than take it apart twice.

Peter

[MattBLancs]

In my experience of broken reluctor ring, the gap was very noticeable - a good millimetre or so between fractured edges - rather than subtle hairline.

Wouldn't think the CV would distort - it's a fair chunk of steel, not really a flimsy thing.

Have you done a "wobble test"?
jack up. Grab road wheel at 3 and 9, then at 12 and 6 positions and see if can get any movement. Would think bearing play more likely to give enough run out for abs ring to sensor contact than a distorted CV??

Matt

[MattBLancs]

Maybe i'm overthinking this but I'd rather go over than take it apart twice.

Peter

Nowt wrong with a good chunk of overthinking, it's cheaper to go through a myriad of options in your head "for free" than dive in without thinking and change parts willy-nilly !

Matt

[peter306]

All sorted, I will never know if I could have got away with just a new reluctor ring as I have a nice shiny new cv joint, sadly it's impossible to see