Peugeot 307 (possible) ABS fault

[quintet]

This issue started around the beginning of the year & was annoying rather than considered an issue, it has however gotten worse of late, it's hard to describe but it kinda feels like the ABS is trying to kick in when the brake pedal is pressed although it doesn't do it each time. There is no ABS light & although the brakes don't quite feel normal (maybe a tad spongy) they basically work as expected.

When I bought this car a few years ago I had to replace the rear brake discs due to a stripped thread in one of the discs, however when I came to fit the discs they wouldn't go on as the ABS sensor was obstructing it/them, I discovered a considerable amount of corrosion behind the sensors so cleaned it all up & put everything back together, there was no ABS issues at the time & it's been ok until recently. What I might have inadvertently done is put off what is generally considered a common problem with these cars with corrosion building up & pushing the sensors out of place, this I think is whats happened now as after inspection I found corrosion behind the sensors again, however no amount of cleaning up is stopping the problem. The sensors have also been distorted/bent by the corrosion, I've replaced the OSR one with a genuine new one but it made no difference, fortunately the sensors are not sided so when fitting the new sensor to the osr didn't work I swapped it to the nsr, however this too made no difference (I may yet put another sensor on it as the original nsr sensor is slightly distorted too but I'm not convinced it'll make any difference) so the new sensor is now back on the OSR.

I don't think I can possible clean the stub axle mounting points any further & even if new ones are available they're probably expensive, won't make any difference and on a 20 year old car probably very difficult to remove the originals which have heavily corroded mounting bolts.

Whilst I have a rubbish diag laptop it has no battery so I cannot do any sort of road test to see if there's any uncharacteristic speed readings.

[ozfrog]

I don't have anything really useful to suggest in terms of the possible ABS problem, sorry. I also have a 307 which gives me strange dashboard messages about the ABS, amongst plenty of other things. That's the real reason I clicked to read your post! But …

Whilst I have a rubbish diag laptop it has no battery so I cannot do any sort of road test to see if there's any uncharacteristic speed readings.

depending on your (financial) resources, you might want to consider a (small?) power inverter that you can plug into the 12V socket and then plug the laptop into the inverter.

There are probably cheaper and easier ways of achieving this same outcome, but that's the one solution I know that has worked for powering my Stephenson's Rocket era laptop.

[quintet]

I don't have anything really useful to suggest in terms of the possible ABS problem, sorry. I also have a 307 which gives me strange dashboard messages about the ABS, amongst plenty of other things. That's the real reason I clicked to read your post! But …

Whilst I have a rubbish diag laptop it has no battery so I cannot do any sort of road test to see if there's any uncharacteristic speed readings.

depending on your (financial) resources, you might want to consider a (small?) power inverter that you can plug into the 12V socket and then plug the laptop into the inverter.

There are probably cheaper and easier ways of achieving this same outcome, but that's the one solution I know that has worked for powering my Stephenson's Rocket era laptop.

For the time being (at least) the ABS light has never come on so making it difficult to ascertain which corner of the car has an issue by running a scan, I like the idea of plugging my ancient laptop into an inverter but I don't know what to opt for regarding the inverter, particularly power wise + it'll be tricky to watch for a drop out in ABS performance whilst driving/braking, I've seen a couple of video's of people doing this and the blip in performance from the ABS sensor lasts only a fraction of a second so any testing will need to be done on a deserted stretch of road (or similar) it does however only happen when the brakes are applied obviously (so not a regular sort of ABS fault) so I can at least try and plan my test.

[quintet]

After a motorway drive today my ABS light came on which oddly I was glad to see as it meant I could find out which corner of the car is having an issue, as it turns out it's the OSF which has a coherence issue, unfortunately despite my best efforts the little bolt holding the sensor in snapped so now I have a bigger problem

I'm not sure what to do right now as drilling out the broken bolt will be difficult, buying a second hand one (hub assembly) is not straightforward as shaft splines differ between models and engines and I also discovered a serious oil leak from the back of the engine somewhere high up and I have another serious issue regarding a recent visit to a garage whom I entrusted to do some work on the car (unrelated to the abs problem) and things went so wrong it may cause the demise of the car.

[quintet]

Apart from the unrelated non ABS issues mentioned in my previous post it looks like I may have fixed the cars ABS issue. The fault with my car was in fact the osf sensor and corrosion behind it, had the ABS light come on sooner I could have diagnosed this much quicker but I opted to go with what I read online rather stripping all the brakes down initially and properly inspecting them. In my own defence the mountings for the rear sensors were corroded and so I opted to thoroughly clean them....before checking the fronts (of which I've not yet checked the NSF) Had I checked all the brakes I might have saved myself considerable time & effort!

Moral of my story, go with your own mechanical gut & don't always rely on what you read online, ie go old school, diagnosis is key.