Rear ABS Reluctor rings

[YPVS]

Hi all,

Does anyone know anything about the rear ABS reluctor rings?

I got a bit of noise after pulling away from a dirty section of road earlier and have pulled up ABS and PSM faults. I reset PIWIS faults for..

0290 Speed Sensor Rear Left Implausible Signal
0287 Speed sensor Rear Right Mechanical Fault

Now after clearing, the noise happened again when moving forwards, after reversing. It's sort of a little clunk on the rear right side.

I've ordered a couple of wheel speed sensors for now, as they're dirt cheap, but the noise is pointing to the ABS reluctor ring, which the sensor reads for wheel speed, as not being in great condition.

Looking at the parts diagram, it does not seem to be it's own part, so must be part of the entire wheel hub, or wheel carrier.

Parts schematic here...

https://www.bellandcolvill.co.uk/deroure?qs=1&preview=1&make=3&model=33&groupid=4402

Has anyone changed these before and knows which part it sits on?

 

[YPVS]

Ah, it seems to be done via one side of the wheel bearing being magnetised. The bearings sound fine, so maybe it's just a leaf or bit of grit causing the noise?

Will pop off the wheel speed sensor when they arrive and have a look.

The bearing looks a right job, needing a 20T press to remove the bearing from the hub, so hopefully it wont need this. If it does, lower arms were an advisory for rust, even though Kurusted, cleaned and painted, so might as well do them at the same time if the hob needs to come off.

 

[YPVS]

Had a little drive this morning to see how it felt. There's definitely something wrong as it's reluctant to change up, holding revs more than normal.

The car starts up with ABS warning before ever driving, then followed by a PSM warning.

I think it's time to move the cars around and use the 996 cab as a daily, putting the 955 under my car port for a wheel off, further investigation, whilst I wait for the wheel speed sensors to arrive.

If it was a wheel bearing though, I'd expect to hear something and I normally drive around with windows down and pan roof open at the moment. It doesn't sound like bearing whine or failure. Maybe the PSM warning is causding the stranger shift behaviour?

 

[infrasilver]

I had to replace mine on the 996 a couple of years ago, I was getting a rumble from the rear and the ABS dash lights.

When I removed the driveshafts I realised the rings had swollen with rust and was wearing the sensors. It was a bit of a pain to get the ABS sensors out of the hub, I ended up getting a bit medieval using drills, heat and drift to get them out. I remember using some "special" glue to fit the rings back on, not sure how special this was or just some blue coloured superglue?

I'm sure the principal is the same for both cars

http://911uk.com/viewtopic.php?t=145230

 

[YPVS]

It looks like I might have dodged a bullet here.

I bought both sensors for around a tenner each. The right hand side needed drilling out as is snapped instead of pulling out. Not too difficult, just gradually drilled out the first inch on the middle until it became soft enough to bend in with pliers and remove the bottom part still intact. The left was straight forward, but I'd recommend taking the wheel off for easier access on both sides.

I had a look inside both holes with an inspection cam and there wasn't much to see. The right side with the "mechanical" fault though, I blasted with a gun on my compressor through the hole and turned the wheel, just in case a leaf or something had got in there.

After replacing both sensors, the faults still remained on turning the ignition on, so I cleared with a PIWIS2 clone. One fault on the LHS would not clear, but that was me being a numpty and not clicking the connector into place, so easily resolved.

No faults with PIWIS2 now so took it for a drive around the block. Did just over a mile so far and all seems good.

Fingers crossed as the wheel bearing on a Cayenne looks an engineering shop job to press out and push in the new one and the wheel bearing seems to have the magnets in which are read by the ABS sensors.

I bought the lower rear wishbone arms and bushes anyway, as they're an MOT advisory and will do those when we get to Autumn, as summer is busy at the moment. They were Meyle ones which IU've used before and the quality for price is great at around £80 each.

 

[Cayenne74]

I have exactly the same as you after accelerating hard from a standstill on the motorway last week. Weird noise then ABS light on followed by PSM fault. Rear left wheel i'm getting the fault code for. Having to shift the car in manual mode. Its into the garage next week anyway for some other stuff so letting them take a look at it.

 

[YPVS]

I have exactly the same as you after accelerating hard from a standstill on the motorway last week. Weird noise then ABS light on followed by PSM fault. Rear left wheel i'm getting the fault code for. Having to shift the car in manual mode. Its into the garage next week anyway for some other stuff so letting them take a look at it.

I swapped both sensors so that could have been the cause, but my issue appeared after I pulled into the central reservation to make room for a broken down vehicle. As I pulled away from the dirty bit of road, it made a noise from rear right wheel and the faults came in.

Before fitting the rear right sensor, I blew compressed air into the hole the sensor goes in. I suspect this cleared whatever debris got caught up in there and suspect this was the cause, not the sensor.

The bearing sounded fine and it's this which has the magnets in it, read by the wheel speed sensor.

 

[Cayenne74]

Very similar experience to me. Crash on the motorway so I was stationary for about an hour in the outside lane. Traffic started moving so I accelerated hard to get up to speed, heard gravel and stones being thrown up and felt something weird happening then the PSM and ABS light came on. I was in 6th gear when this happened so the gears changed fine all the way home. It was the next day when I read the fault codes and cleared them (then they came back straight away) that the car then started holding gear and I had to go to manual shift mode. I'm assuming that's due to the rpm fault it's giving me from the sensor. Code for that is 1681 'RPM signal for left rear wheel. Speed sensor code I got was 0290.