Hi guys,

I've just had my Octavia back from the garage after getting a new gear box and clutch fitted. One of the first things that the mechanic said was "Do you know that you've got a problem with your ABS pump"? Now, before I went in I had never noticed any problems braking, and my wife drives the car every day for a fair distance and never reported any issues either.

However, when I drove away from the forecourt the ABS light was on on the dashboard. I phoned the garage and explained to them that this was NOT on prior to me putting the car in to get work done and they've said that they will "Take a look" but claim that nothing to do with the ABS could have been messed with during the fitting of the gear box and clutch.

Do any of you have any experience with anything like this? Any help would be gratefully received as I am not mechnically minded at all!

Many thanks in advance!

Iain

Could be one of a many of things. You really need a diagnostics check running, does someone have VAGCOM near you??

They will have disturbed the driveshafts, but short of damaging an ABS sensor they wouldn't of touched anything ABS related... :rubchin:

Sadly I'm not near one of those, but the garage are presumably going to check it out (they said that they would do so for free).

The scary thing is that the ABS pump has really started pumping when you brake, so much so that I've removed the fuse to disable it (as it feels very wrong). Is this stupid and daft?

I would be willing to swear on my life that this wasn't happening before I put the car in so if anyone could give me any pointers as to what could possibly have gone wrong that would be great!

Could a damaged sensor make the pump behave like this?

Iain

Hmm... I've just read that the sensors for the ABS regulate how the pump works. Would damage to one of them cause this sort of behaviour?

Dunno about the Octy, but Fabias have a common brake / clutch reservoir so if you mess with the clutch hydraulics on a Fabia, you may have to bleed the brakes and vice versa.

Might be a red herring.

i had the same prob it was the sensor on the hub carrier that was bent

could also be dirt on the sensor clean whith a dry paint brush

Cool - are their any diagrams/photos anywhere showing where that is? Does it involve taking the cover at the bottom off?

I always thought that when the ABS light was on, you lost the anti-lock functionality of the brakes - with this the pedal would not pulse. The ABS sensors regulate nothing - they communicate to the control unit the wheel speeds and it is the control unit that tells the hydraulics what to do. I can't see them really going near the sensors as they will unbolt the driveshafts at the flanges on the gearbox, if they did remove a driveshaft it is very likely to have been the left one.

I am inclined to think that it could be a terminal 30 fault - there is an electrical connection between the air filter housing and the battery, as I suspect that they may have had to remove the battery and/or air filter this plug could have been dislodged.

The clutch fluid take off on the brake master cylinder reservoir is high enough so as not to allow air into the brake hydraulics.

Edit - don't forget to replace the fuse when they check it.

Thanks for the tips. I'll post tomorrow and let you know how I get on.

They shouldn't have needed to touch anything other than the wheel sensors (and damage there will indeed turn the ABS off). However, I'm not sure what might be strained if the engine tail wasn't properly supported whilst the box was out of the car.

Well, good news! Seems that all that was wrong was that one of the driveshafts (I *think* that's what he said; I was too busy exhaling in relief at the time) was slightly out of alignment which was causing the problem. They sorted it there and then for no charge and now it's peachy again!

As a big plus to the garage, the customer service was absolutely excellent. No quibbling or anything. They simply took a look and sorted things.

Many thanks to all of you who took the time to read this and offer advice!