Hi all,

What a title! It has it all - drama, suspense, plot, pace, atmosphere...

 

OK, back to reality. It's a Mk II Fabia TDi estate, 62 plate, about 103k miles. Discs and drums, alloys with Toyo Proxes T1R in good nick with lots of tread.

 

I started to notice a droning noise (not coming from any of the seat occupants) which starts at around 30mph and continues up to around 60mph, irrespective of what gear the car is in (including drifting in neutral). The tone/pitch does not change noticeably with speed, though at around 40-45mph I have noticed a slight "pulsing" in the noise.

 

It initially seemed to come from the rear, so I changed both rear wheel bearings. No difference.

Then thought it was coming from offside front. Changed that wheel bearing. No difference, except that now the ABS is not working either.

 

Re the ABS failure. I popped the ABS sensor before pulling the bearing out, and it has gone in (and out and in) again with no difficulty and no signs of damage. The replacement wheel bearing wasn't an Ebay "cheapest deal going, made of authentic Chinesium" but bought in person over the counter from an established 'chain' motor factor and specifically matched to the registration number and so should be completely compatible with the ABS.

 

I am starting to get a bit wound up by it, so any help will be very much appreciated!

 

 

I had this on mine (droning) so as a matter offcourse replaced as you did both rear wheel bearings as it sounded like that from previous experience........., made it "better" but not perfect.

 

Anway tracked it down to the continental tyres in the end. You could try swapping front and rear wheels and see if that helps / changes the sound and maybe narrows it down.

 

REF ABS fault, unfortunately there is far to many aftermarket hubs for ALL makes of cars and many of them simply do not work as advertised.

Messing with the sensor probably won't do much, the fault will be latched and most likely needs A) plugging in to see what the fault is and b) clearing it if its not a current fault.

Edited 17 April, 20215 yr by UrbanPanzer

Did you use the appropriate tooling to fit the hew front hub/bearing? It's a bad idea to press these in by pushing on the hub face.

Hi and thanks for this. Glad it's not just me!

 

I am going to try swapping the tyres round front/rear and side/side in the hope that makes a difference. The Proxes are marked "inside/outside" rather than being 'handed' left/right, so I can swap to my heart's content. I've run Proxes on a previous car and never noticed noise like this - but it was a genuine (road legal) racing car (MR ZR), so the noise levels were - erm - high already.

 

Re the ABS, a mate has a Gucci OBD reader and read off "RHS Front ABS sensor implausible reading" - he cleared the fault, but it's returned every time I've driven the car since. So unless the sensor has packed up (which would be something of a coincidence) it looks as if the bearing doesn't have a working rotor 

 

Have to say I'll be more than a bit hacked off if the only solution is another replacement wheel bearing. Skoda quoted me (I only rang them up for entertainment purposes) about £160 plus VAT to supply the bearing/hub (fitting was relatively modest at about £150 plus VAT, but I did start wondering if the bearing was made of Unicornium and packed with Myrrh  

3 minutes ago, Wino said:

Did you use the appropriate tooling to fit the hew front hub/bearing? It's a bad idea to press these in by pushing on the hub face.

Hi Wino,

I used the 'collar' tool that looks a bit like an orthopaedic knee brace, to draw the bearing in. It puts all the load on the shoulder behind the spring clip, so no pressure on the hub face and no load being put through the bearing itself.

to be fair, if the new replacement hub is faulty, return it.

As mentioned it could be the bearing at fault, i fitted a   bearing and my ABS would not work, bearing was from a well known chain, borrowed a new sensor to try and this fault was still there, tried my sensor on my mates car that needed a replacement and hey presto worked ok so fault was with bearing, stripped it apart and could not see any damage but fitted a new bearing from SKF which did cost a lot more but sorted the ABS issue out, a costly mistake but won't make that one again, it seems that the ABS ring did not have the correct spacing for the sensor to pick up the gaps and threw up a fault on the system

13 minutes ago, UrbanPanzer said:

to be fair, if the new replacement hub is faulty, return it.

Yes, that's an option...  but I hope it's not that as it'll be a major hassle. I'll need to get a new ABS sensor to confirm that it's the hub that's faulty, and find another hub that works, and swap them over, as I need the car to stay mobile... Not a five minute job and a lot of hassle. And as this hub will be wrecked by removing it again, the seller is likely to be arsey about it. And I don't know if I can find the receipt!!

1 minute ago, Murdockman said:

As mentioned it could be the bearing at fault, i fitted a   bearing and my ABS would not work, bearing was from a well known chain, borrowed a new sensor to try and this fault was still there, tried my sensor on my mates car that needed a replacement and hey presto worked ok so fault was with bearing, stripped it apart and could not see any damage but fitted a new bearing from SKF which did cost a lot more but sorted the ABS issue out, a costly mistake but won't make that one again, it seems that the ABS ring did not have the correct spacing for the sensor to pick up the gaps and threw up a fault on the system

 

seen it far to often.

Fantastic.

So I've buggered the car up, and it probably wasn't even the wheelbearing that was at fault...

Thanks guys. I was a bit afraid this would be the case. Oh well.

not for sure................

 

If you need / want a genuine hub, one here cheap.......I don't know the OEM manufacturer otherwise it would be easier to source the same part cheaper...........it "may" be SKF (see below)

 

https://www.ebay.co.uk/itm/VW-Polo-Audi-A1-Front-Wheel-Hub-with-Bearing-72mm-6R0407621A-New-Genuine-part/114643147506?hash=item1ab1439af2:g:ajwAAOSwJk1gCeJE

 

Or this I would have faith in being SKF....

 

https://www.ebay.co.uk/itm/SKF-FRONT-WHEEL-BEARING-KIT-SEAT-AUDI-VW-SKODA-OEM-VKBA3569-6R0407621A/264685108160?epid=1563460430&hash=item3da0763bc0:g:-oEAAOSwDDdeg35x

30 minutes ago, UrbanPanzer said:

 

seen it far to often.

 

Is the difference between the old & the new non functional ABS ring visible in hindsight?

mmmm interesting..........who knows.......Without seeing the "actual" SKF part its hard to say.

 

Personally and I know its painful due to cost, but with stuff like this I always buy genuine because it works out the box.

Iirc its important you remove the ABS sensor before you remove/refit the bearing as it can get damaged.

 

3 yrs ago I bought a FAG 713610470 bearing kit for £40 from ebay and had it fitted my dealer for £94. 

 

 

 

 

 

Sadly my dealer will no longer fit customer supplied parts.

Edited 17 April, 20215 yr by xman

Morning all,

 

Thanks again for all the responses. Sorry if my last post last night sounded grumpy!

 

I did pop the sensor yesterday before removing the bearing, and it went in cleanly afterwards. We (my assistant Pete the Badger and I) did note that the cable went through a tight angle onto the sensor (the cable could have been routed more kindly!) but there was no evidence of wiring damage. After the first road test yesterday and first indication of an ABS problem, we went back, popped the sensor again - but there was no visible sign of damage to the sensor or wiring then either. We took it out again after that, exactly the same again (ABS light went out on starting, but then came on as we went up the road, stayed on).

 

Interestingly, I just went out to the car and when I started it, the ABS light came on instantly and stayed on, even though the car didn't move (which says to me that irrespective of whether there's a problem with the rotor, there is another problem now?)

 

In passing I had attempted the wheel bearing change earlier in the week, but stopped at the driveshaft as I couldn't at the time get the shaft out of the hub, so at that stage I had removed the ABS sensor and refitted/reconnected it, and it was fine after that.

If the ABS light came on without moving the car, there must be a permanent electrical fault somewhere on the ABS system.

 

Either the ABS block itself, or one or more ABS sensors electrically faulty.

 

You need a scan from VCDS to identify the problem/s.

42 minutes ago, PipH said:

If the ABS light came on without moving the car, there must be a permanent electrical fault somewhere on the ABS system.

 

Either the ABS block itself, or one or more ABS sensors electrically faulty.

 

You need a scan from VCDS to identify the problem/s.

Hi Pip,

Yes, starting to think it's not necessarily (only) the rotor on the new wheel bearing.

The fault seems to be a bit haphazard, I've done several short runs, and one longer one, today; some of the times the light and warning message have come on immediately, on other occasions it's come on after I've driven off (once when I reached about 35kph, once at 47kph, once at about 57kph).

Pete the Badger (as per one of my posts last night) has an OBD reader and connected it to the car yesterday, that read the fault as "RHS Front ABS sensor implausible reading" - I suspect if it went on now it might read something else indicative of a failure - quite possibly the RHSF sensor. However carefully they are handled, they do seem to dislike being disturbed. I have another one on order (only another tenner on top of everything else I'm haemorrhaging money over at the moment) which should arrive this week. 

 

PS in my world, VCDS is Vice Chief of the Defence Staff - not sure if he drives a Skoda :-D :-D :-D 

Check the abs connector. I have had the same problem in the past and when the connector was parted it threw up the fault. Check everything is clean and tight on it.

4 hours ago, mpm222 said:

Check the abs connector. I have had the same problem in the past and when the connector was parted it threw up the fault. Check everything is clean and tight on it.

Thanks. I'll be back at the workshop tomorrow, so can do that as well as trying out the 'swap the wheels round' game

UPDATE

Re the droning noise - Tried swapping the wheels round, no change.

 

Re the ABS - one of the others in the workshop has an even more Gucci code reader with comprehensive diagnostics, able to read the speed reading off each of the ABS wheel sensors. Comparing the NSF and OSF, the OSF (AKA my problem child) delivers intermittent, momentary dips in the recorded speed, while the NSF trace is smooth. Looks for all the world like a dodgy connection somewhere. The fact that most of the time the traces align, says to me that there's nothing wrong with the rotor on the bearing (thankfully).

Nothing's been disturbed except at the OSF hub/upright. I've changed the sensor head itself but that made no difference. The wiring going onto the sensor, though, is taken round a tight angle onto the connector plug, so it's got me wondering if that cables have crimped and it's broken one... That cable wraps round the upright and then up and onto the back of the wheel arch, disappears behind a cover - so I'm hoping there's another connector behind the cover, so I can detach the whole of that cable to test and replace/repair...  

 

surely if the cable was damaged it would show a constant "error" as opposed to an intermittent one,

 

Edited 22 April, 20215 yr by UrbanPanzer

Only if it was broken completely.

 

TBH I'm struggling for other answers at the moment

No intermediate connector unfortunately. Direct to connector at ABS module:- pins 1 and 2 at wheel sensor to pins 6 and 18 respectively at module. 

I'd be tempted to harvest connector plus a wheel-archful of wire from a scrappie car and cut and shut that in, waterproofing connection area well.

12 hours ago, Narrowboat-Ian said:

Re the droning noise - Tried swapping the wheels round, no change.

Not being funny but have you tried an olde-fashioned "rock test" for wheel bearing wear? Based on discussion so far, starting with the OSF.

Out of pure curiosity, Narrowboat-Ian, have a try of driving the car so the ABS is on, switch off the key (In a nice safe place) For a few seconds, then turn it on again, so the engine re-starts the car, not the key/starter motor. Then see if the light goes out at least for some time or if it stays on as soon as you turn on again, if you get my drift!

 

Kind of bump-starting the car, after initial driving.