DSC Hydro Unit and Vacuum pump

[valentino]

Oh joy!

Couple of problems, my brake warning light that had illuminated was a failure of the DSC Hydro Unit. Not cheap... Anyone heard of this? Apparently it is a known problem on other BMWs but the unit is repairable - bit not on the Z4, its one unit! Typical..

Also I have a faulty vacuum pump - so this requires a new pump and rocker gasket (£70 + for a gasket?!!! wtf?!!!) Ideas where this thing is and what it does?!

So thats my happy news... I feel a trade in coming on.... :x

 

[mac27040]

is this what your looking for:

http://www.ebay.co.uk/itm/Fuel-Vapor-Leak-Detection-Pump-for-BMW-x3-x5-x6-z3-z4-z8-Series-2002-to-2012-/280983426971?pt=Motors_Car_Truck_Parts_Accessories&hash=item416bead79b

http://www.ebay.co.uk/itm/BMW-E85-Z4-3-0i-2003-ABS-DSC-Pump-34516762867-ECU-6762868-0921-/200748079231?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2ebd84987f

 

[sam1832]

The vac pump sits on the back of the block on the left hand side (the drivers corner of the engine)

It's connected by a shaft to the end of one of the cam shafts, which turns it,

Is this an n42 engine?

What up with the pump? Oil leak? if its leaking there is a gasket on the face of it, under 4 torq bolts

The gasket can not be bought separate. You need to buy the whole vac pump, however there is a gasket from something else that is the correct size, I will try and remember what gasket it is


Sent from my GT-I9300 using Tapatalk 2

 

[bcworkz]

The vacuum pump is required on the N52 because no conventional manifold vacuum is available due to the way the Valvetronic mechanism operates. Engine vacuum is used to operate various mechanical bits, most importantly the brake booster.

 

[valentino]

@mac27040 the first thing isnt, but the abs pump is, but the 2.0 has a different part number, so I assume they arent interchangable.

The vacuum pump is leaking which mught explain my lumpy tickover and stuttery accelaration. A new one is about £300 or there abouts, but there is a modification as its a known problem.

As for the DSC hydro unit, I did a bit of digging last night and it seems like a posh name for the ABS unit. Its a commong failure on other BMWs but not on Z4s and there is a repair kit for EVERY other model except the Z4!! New ones have a modified DSC HU. However, my fault is really odd. DSC and ABS still work, only the 'hill hold' has failed. So since its not life threatening I'll look out for a second hand one and repair it before the next MOT. Doesnt look like a big job, and the labour charge backs this up. Pity the thing is so expensive!!!

:x

 

[Seand411]

I had this problem a month back ... Had 3 yellow warning lights on dash (AbS, traction control,handbrake) turned out to be a faulty dsc module. £1400 plus VAT for the part. £1970 from my local BMW specialist and £2070 from BMW Sytner Nottingham. Nearly cried!!

However... Due to my car being well maintained by BMW I.e inspections completed when recommended Sytner completed a good will request to BMW. A week later had news that BMW would contribute 80% of the part. So the bill came to £699. Still a lot of cash but far better than 2grand!!

Going back to MOT. If your abs light is on it is an instant fail on mot.

A second hand dsc module are available on eBay however it will need coding to your vehicle, unsure whether BMW would do that due to the item being second hand..

Hope you sort it!!!

 

[DrNick]

My hydraulic pump also failed recently - Snows did all the hard work for me and got BMW to pay for 80% of part and they discounted their labour so total bill for me was £430.

Sean copied me after reading about it on here...

 

[valentino]

Sean and Drnick!

Bad news... goodish news... then slightly less painful bill. Well done BMW, my car is years old, doubt they will be so accommodating!!

I dont have any issues with the DSC or ABS, they are working fine, just the hill hold.. strange!!

 

[HAL296]

@mac27040 the first thing isnt, but the abs pump is, but the 2.0 has a different part number, so I assume they arent interchangable.

The vacuum pump is leaking which mught explain my lumpy tickover and stuttery accelaration. A new one is about £300 or there abouts, but there is a modification as its a known problem.

As for the DSC hydro unit, I did a bit of digging last night and it seems like a posh name for the ABS unit. Its a commong failure on other BMWs but not on Z4s and there is a repair kit for EVERY other model except the Z4!! New ones have a modified DSC HU. However, my fault is really odd. DSC and ABS still work, only the 'hill hold' has failed. So since its not life threatening I'll look out for a second hand one and repair it before the next MOT. Doesnt look like a big job, and the labour charge backs this up. Pity the thing is so expensive!!!

:x

I have a just been told after BMW maintenance check that my Vacuum pump is leaking oil and cost likely to be around £500 - you mentioned there is a modification as it is a known problem - can you give any more details please? The garage is saying lack of use is cause as my Z4 Roadster does only 2000 miles a year.

 

[foxy-stoat]

Have an ABS pump going for £25 (giving it away!!!)....loads cheaper than another on ebay! I can get the part number up if you need it.

 

[tabbie]

Any updates on this problem with the abs hydraulic pump? Afew posts mention cleaning the abs sensors on the wheels sometimes clears the fault codes or should I face the fact my zed is going to bankrupt me yet again. Thanks for any advise.

 

[hornbyrob]

My hydraulic pump also failed recently - Snows did all the hard work for me and got BMW to pay for 80% of part and they discounted their labour so total bill for me was £430.

Sean copied me after reading about it on here...

@Sean @Drnick both, just been quoted for the same issue at £2100 fitted via BMW. Seems to be a common failing and just wondering how you got them to discount? I've written BMW Customer services a mail on the subject and they have denied it being their issue (my car has only done 30k and is fully serviced and not thrashed - maybe that's the problem) and also the dealership hasn't really offered much option other than the repair and a 10% level of goodwill. Tried the cleaning and sensor issue, so is definitely a fault. Not had much luck with the car so far, been knocked, scratched and the springs have gone (my love of the car is fading).

Any chance you could message me with any kind of formal response. Thanks in advance.

 

[AndrewP]

Sorry to hear that Rob, I got 80% goodwill contribution on the DSC unit too but it was the dealership (Eastern BMW in Edinburgh) that did all the contact with BMW and got the goodwill up from the initial goodwill offer of 50%. My car was 5 years old and 43k miles at the time, FBMWSH too, and I mostly spoke to them on the phone when pushing it mentioned that I was disappointed that my first BMW, with low miles and service history, had such an expensive part fail and I expected better of the brand. Maybe try a different dealer if there's another one nearby or that the car's been serviced at in the past?

 

[hornbyrob]

Thanks, will give them a call in the morning (BMW) to see if they can follow up. It has been serviced (one time I've had to do it) via a Bosch accredited centre. Will try that line but seems such a common issue that not sure how they can say it isn't something they will fix more cheaply There isn't another dealer close to where i live (same dealer, might go via customer services as well tomorrow). :thumbsdown:

 

[hornbyrob]

Thanks, will give them a call in the morning (BMW) to see if they can follow up. It has been serviced (one time I've had to do it) via a Bosch accredited centre. Will try that line but seems such a common issue that not sure how they can say it isn't something they will fix more cheaply There isn't another dealer close to where i live (same dealer, might go via customer services as well tomorrow). :thumbsdown:

Result, 50% discount and have the old hydro in the boot, think it is sellable as seems to be a few reconditioning sites about....