PSM/ABS light on, rubbing noise, potential issue

[infrasilver]

Before my engine let go last year I remember having the PSM/ABS light come on and as my car is now complete and is ready to be dropped to the floor for the first time for nearly 9 months I thought it a good idea to try too find out why this was on and I also remember having a feeling through the car while driving, I had put this down to the IMS after that decided to go AWOL.

I have been driving the car through the gears while up on stands, just checking for leaks and bleeding the coolant but I can feel a rubbing through the seat when driving the rear wheels, I have put the car in 3rd gear and got out the car to check everything while the discs are spinning and I can feel the issue through the nearside rear caliper when I put my hand on it, this is the only thing I could touch while everything is spinning. I thought it may be a sticky caliper piston so I levered the pads away from the discs but I am still getting the rubbing and noise, it happens once every revolution?

I know the ABS/PSM light would normally go out after a mile or so of real road driving but I have a feeling I have an issue that needs sorting and it makes sense to try to investigate while it is still in the air.

What issues are caused by a faulty ABS sensor or reluctor ring, or is there anything else I should be looking at?

 

[infrasilver]

I should also mention the speedo isn't working, I can't remember if it should when just the rear wheels are being driven but worth noting it doesn't currently work while driving on the stands.

 

[MisterCorn]

I can imagine that a broken reluctor ring would cause these sorts of issues.

MC

 

[coullstar]

Was just what I was thinking. I had one in another car that was split and when at low speeds ABS would kick in.

 

[L1OFF]

I had PSM \ ABS fault when my MAF plug was not quite pushed home properly.

 

[infrasilver]

I've had a look at it this afternoon and found the car was sort of in limp mode when I had it in gear to drive the wheels and I could hear the grinding as I mentioned but still couldn't pinpoint where exactly it was coming from.





You can see the ring reluctor is still in one piece and was in decent condition, it's only when I spun the driveshaft after removing the hub nut that I saw a shiny bit that must of had some corrosion build up underneath it and swelled the ring in turn catching the ABS sensor.

The speedo did actually show speed when I had removed the ABS sensor and ran the car again so that is pointing at the sensor also being damaged.

I will need a new sensor too, plus I will do the other driveshaft while I am messing about with this one as that can't be far off causing a problem and a couple of new hub nuts will be required, I'm assuming you can't re-use them?

Any tip on removing the drive shafts from within the sub-frame without removing too many suspension arms, can it be removed by just undoing the inner coffin arm bolt or will more need to come off, it's stuck at the moment until I start removing parts.

 

[infrasilver]

Dug deeper with this yesterday and also found the off side reluctor ring is swollen and was catching on the sensor too, so looking like another new sensor is required. It took some doing getting the driveshaft out on that side and I ended up removing every suspension component to remove the hub completely, the only things I didn't remove were the brake line and handbrake cable to get the driveshaft out

But now I have done this I noticed the inner coffin arm adjuster bolt was free but the hole it moves into when adjusting was full off corrosion so wouldn't spin all the way around and the top link dog bone bushes all seem to be delaminating. So it look like a minor overhaul of the rear suspension is in order before I can get this thing back on the road!!

There is no play in the top links arm bushes but I was looking at poly bushes for them and I'll just clean up the lower adjustment hole. Luckily everything unbolted easily because I had copper greased all the bolts in this area around 8 years ago.

This car loves spending my money...

 

[infrasilver]

Other driveshaft is off and there was no other way around it other than to remove every part of the suspension again, I was hoping I might find an easier way.

Both have shiny wear marks on them but haven't split, you can see where the rust has swelled then out.

Dog bones all delaminating so will get new poly bushes fitted, just need to order those ASAP

The speed sensor bolts came out easily which was a surprise but then getting the sensor out itself was a different story, I had a go at getting the first one out in one piece but ended up smashing it off and I'll have to drill the remainder out, I will probably have to do the same to the other side?

I guess it'll take a week to gather all the parts I need so I can finish this off.

 

[Alex]

Reluctor rings are only a few quid. Give them a good blast with the rothenberger before pressing them on. Helps if you have someone rotating the drive shaft whilst you evenly tap it on.

 

[infrasilver]

Well this is turning into a bigger job than I had envisaged although I would rather get these done while they are off. I have stuffed the CV joints with fresh grease as there wasn't an awful lot in there as you can see from the right one in picture and I'll replace the metal straps that hold them on. I've also been prepping and painting the rust on the CV's and the shaft itself.

I have the reluctor rings but I'm waiting for the paint to dry to fit them and also some bonding fluid to arrive, I hadn't bought any when I got the reluctor rings. The old rings were crusty but easily came off with a hammer and chisel.

I had to chip the loose rust off with a chisel hammer then get the angle grinder wire wheel on the CV's and shaft before painting.

Before and after

I thought I could drill the speed sensors out but I didn't have any luck doing that, it didn't even scratch the surface of the magnet and drifting it out didn't work, I ended up heating the aluminium up around the sensor to melt the outer part of the sensor then I was able to drift the centre magnet out but then had to drift the rest of the plastic out with a screwdriver and clean the inner bore with a wire brush in a drill. What a faff getting these out were but understandable as they had never been removed in its lifetime.

While I had the pointed wire brush in the drill I cleaned up the adjustment slots for the inner coffin arms as they were also corroded and filled with crud from the oxidisation build up. You can see how filled up they were in this before and after.

As for the dog bones I'm going to fit new poly bushes to them but may wait a little to do that as there isn't any play in them currently and I don't want to keep chucking money at it at the moment and I do need to start running the engine in at some point this year.

I have a plan to make my own bushes just because I have never made my own and it'll also save me a few quid so this will be something I'll do in a few weeks before I get the geo set again.

 

[infrasilver]

Finally sorted these driveshafts out, new reluctors fitted and both ABS sensors changed and drove the car up on ramps again, there is now no rubbing at all. I just need to drop the car off the ramps tomorrow and head for the Peak District.

Drive shafts refurbished, they look so much better now.

Reluctor ring lines up correctly.

I had painted the whole CV joint but then thought that the inner ones have bolts holding them to the gearbox so it was probably a good idea not to have any paint there, so I wire brushed the paint off where the banana washer sits.

ABS sensors part numbers.

The state of the rears has made me wonder how bad the fronts are so I may look at those soon.

And with that mini saga over I should be good to tax and insure it in the morning and start the running in process, although I have already done 8 miles so far just in the garage.

 

[Alex]

Good stuff Chris. From experience the rear end gets far more hammer from the road/weather than the front so I'm guessing your front sensors/rings will be in much better condition.

 

[abe996]

Nice work bud! :thumb:

 

[infrasilver]

Just to add I finally torqued the hub nut to around 460Nm or as it was my full body weight on the end of a scaffold tube.