Now my poor scout doesn't get much driving done of late due to other cars in the fleet but decided to take it out for a run.

As I drove off the drive it lurched a little and he abs light flicked on then off again. About a minute later it came back on for about 30 seconds and went off. 

As nothing seemed immediately wrong I kept driving I wasnt going far, but near the end of my journey at about 40mph the steering started shaking. Felt like a flat tyre. So I slowed down and limped to my destination. Checked tyres but nothing obviously wrong, but front nearside was hot and smoking.

 

Aha! Stick caliper me thinks. Popped off to do what I was out to do came back to the car 30 mins later. No fault codes on my generic reader and the car easily moves being pushed with a leg out the door so not obviously stuck caliper.

 

Took the slow route home (2miles ISH) and by the time I got home front nearside disk was again very very hot but not obviously sticking.

 

Immediate thought was because of the weird little jolt I got coming off the drive something off with the abs and it's triggering the brakes somehow. 

 

I've booked it into the garage but does anyone recognise similar symptoms? Quick search suggests faulty/rusty abs rings are pretty common but not quite the same symptoms 

 

Thanks all!

How do the wheel bearings feel on that side?

9 minutes ago, Warrior193 said:

How do the wheel bearings feel on that side?

 

Thanks for replying, To be honest I haven't checked! Would failing wheel bearings make the abs light flash up? Disks and pads were changed a couple of thousands miles ago (nearly 70k on original pads!) so it doesn't have a hard life.

Edited 12 July, 20241 yr by goatboy

I've not seen what the ABS sensor clearance is - but I'm guessing not large - excess float in bearing could conceivably change gap sufficiently to trigger fault.

As the pad to disc clearance is also very small, worn bearings could be causing excessive contact.   

2 minutes ago, Warrior193 said:

I've not seen what the ABS sensor clearance is - but I'm guessing not large - excess float in bearing could conceivably change gap sufficiently to trigger fault.

As the pad to disc clearance is also very small, worn bearings could be causing excessive contact.   

Nice thinking, thanks 

 

Worn bearings or warped discs will simply cause piston knock back on an otherwise non faulty braking system, this would manifest as long pedal travel when braking after travelling a distance.

 

Noticeable heat compared to the other side is either uncommanded brake actuation or a sticking caliper piston, you cannot rule that out as you did not try pushing the car straight away when you stopped or with the engine running.

 

It sounds like a wheel speed sensor issue, you will need VCDS or a similar level diagnostic tool to interrogate the ABS controller to investigate any further, as it has yet to show a MIL light on the dashboard it will probably need live data running to compare all reported wheel speeds.

 

Otherwise wait for the MIL light then change that wheel speed sensor or do it as a pre-emptive measure, they cost less than €2 from China and work just fine regardless of what people say.

Uncontrolled brake actuation was my gut feeling. I'll look into wheel speed sensors. Are they an easy job?

If they come out without snapping then yes.

 

With experience you can tell whether they are going to remove or snap before applying too much rotational force and with patience and experience again you can wiggle them just enough so that a penetrating agent can work its way through the joint without fracturing them.

 

The only way you gain that experience is having broken a few 😢

Don't like the sound of that much!

Well it turns out I was completely wrong, left front caliper seized taking the disc and pad with it. A faulty speed sensor on rear near side found too but believed not to be related.

 

Car all sorted now and driving great. I wonder how long it had been sticking, seems so much smoother and quieter now but I know that might just be a placebo....

 

Thanks everyone for your help 

Edited 20 July, 20241 yr by goatboy