Haldex issue

BennyG_UK

Top Gear
VCDS Map User
For some reason on the way to work this morning quattro decided to pack up, lots of wheel spin when I never ever used to get any at all.



Plugged my VCDS in at lunch time, no fault codes relating to haldex at all, just a lamba sensor and battery voltage low thats it.



Did output test on haldex with vcds and heard the pump as expected, and pressure and temp display as expected too.



Stumped
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Anybody have any ideas? Will check traction on way home again but defiantly wasn't right on the way to work.
 

BennyG_UK

Top Gear
VCDS Map User
Bit of further info:
Jacked up rear end, did output test in vcds to 'engage' coupling which does stop the wheels moving freely, but with enough force you can still turn them by hand. Looking at the pressure it only seems to be around 4-5bar and in the range on vcds it saying up to 40.

So I guess its either pump or fluid level?

Ive looked underneath and whilst it looks like there has been oil on the haldex it looks old not fresh.

Any haldex gurus around that have any ideas what I can check next?

Oh, and still no fault codes at all since I cleared earlier today!
 

s3_sid

Registered User
Would alsobe nice to know I have exactly. Same issue happens to me a week ago , was haldex serviced like 8k ago
 

BennyG_UK

Top Gear
VCDS Map User
Yup mine was serviced about a year ago. Cars done about 6k since.

Have you checked the pressure with vcds? Is it similar to mine?
 

s3_sid

Registered User
Yeah did the output check can hear the charge pump and had similar pressures to you about 4 bar never jacked it up to check clutch pack but I assumed all was well , takes me back in time spinning up everywhere I go although I do like hestiation noise trough the exhaust when traction control is on , I'm easily amused !
 

BennyG_UK

Top Gear
VCDS Map User
Haha it does make some interesting noises.

Really want to get this fixed though. Holding off powder coating my new wheels in anticipation of a huge bill :(
 

s3_sid

Registered User
Lucky I have a used low mileage diff sitting to go in but as haldex yeah evn though I get a good price on bit through my tps account and fit my own stuff I still see it being expensive and could just keep going through parts untill you find the problem
 

BennyG_UK

Top Gear
VCDS Map User
Lucky you. Had a quick look on eBay and nothing gen 2 related :( theres a complete rear drivetrain from a 2011 but thats a completely different generation of haldex
 

s3_sid

Registered User
I only have a diff no haldex unit , woukd like to see how hard it is to convert second to 4th gen ,
 

BennyG_UK

Top Gear
VCDS Map User
Have you changed your pump yet? I think mine is either pump or controller. Changed oil at weekend and its now working randomly.
 

BennyG_UK

Top Gear
VCDS Map User
Yea same thing. Well I'm on day two and mine seems to have started working again by itself. All that I did was change oil and leave the output test running for about 5mins on vcds and all appears to be good now.
 

s3_sid

Registered User
so you just put oil and filter and new pump in , you get a new pump ? If so how much was it, Also could you hear the pump running before you changed it ?
 

BennyG_UK

Top Gear
VCDS Map User
Nope still on original pump. Could hear the pump before hand. All I did was change oil and left pump running for 5mins via output test on vcds. Going to change oil and filter again in a week just to be 100%
 

s3_sid

Registered User
hmm wonder where the fluid has one though ! , wonder if its leaking into the diff ? , mine is dry as a bone
 

BennyG_UK

Top Gear
VCDS Map User
Thats the thing, mine had plenty of fluid in when I changed it. Probably more than what you get in them tubes to re-fill! The only thing I did notice was plenty of metal substance on the drain and inspection plug (they're magnetic) But no idea how long thats been there only had the car 6 months but supposedly the oil was changed by audi last year. Though the oil filter looks like its never been changed!
 

s3_sid

Registered User
Hmm I'll have a look , just scanned it and it had a clutch maulfunction intermittent , checked Ross tech wiki but the code brings nothing back so back to the drawing board
 

BennyG_UK

Top Gear
VCDS Map User
Weird, well mines working fine now, no blips at all past few days.
 
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