Haldex competition controller and abs problems

[racin2redline]

Ok let me start of by saying I already know there's a fault in my abs system I haven't been able to locate anyone with a vag com around me, could be the steering angle sensor or a speed sensor? The fault has been here since before I installed my competition controller. I realize there was going to be some binding with the competition controller that goes without question but I'm wondering if whatever the issue of the abs system may be is affecting the operation of the controller? For instance turning around a normal 90 degree turn ( not even close to full lock) on the street the car will go around the turn normal but as your straightening out the wheel the car will begin to hop forward I'm not sure if this is just the nature of the controller being the car is trying to rotate the front wheels at a different rate than the rears or if the controller is not receiving a vehicle speed or a sterring yaw angle from the abs unit ? But either way I've done some research and I've not seen anyone with the same issues I'm having ( if someone. Is please chime in)

[Marcus_Aurelius]

I have heard of it! It is binding at low speed and high steering angle. Search the R32 forum and you'll find plenty of returns on the subject.

Just sell me your controller!

[DougLoBue]

Both Max & me have VagCom on LI. I currently have it in my trunk of my car with the laptop.

PM me if you want to meet up.

[racin2redline]

I think the issue I'm having is more the abs.. I believe that the haldex ecu uses input from the abs system such as steering angle and wheel speed so if those inputs aren't there the unit doesn't know when to unlock or release some pressure to allow a certain amount of slip. Obviously there is going to be binding you have to think of a locked haldex as a truck in 4wd on pavement but not as intense.

[20v master]

I think the issue I'm having is more the abs.. I believe that the haldex ecu uses input from the abs system such as steering angle and wheel speed so if those inputs aren't there the unit doesn't know when to unlock or release some pressure to allow a certain amount of slip. Obviously there is going to be binding you have to think of a locked haldex as a truck in 4wd on pavement but not as intense.

I think you're correct. The binding issue is usually seen at slow speeds and extreme steering inputs, think parking lot maneuvers. If you're doing 30 mph and making a normal 90* intersection turn, I don't think the binding would be there. Now why you got an ABS fault on install of the controller, I have no idea, but you obviously need the ABS system scanned for codes. Why would the steering angle sensor or vehicle speed sensor be affected by the install of the Haldex controller?

[racin2redline]

the abs fault was there before i installed the controller im prety sure thats related to the problem im having before the installation the haldex unit performed perfectly

[Chuckmeister87]

I have an issue with my competition controller as well. When the car is off and on a lift, if I spin the back tire the other rear tire does not spin at all. I was pretty sure the other rear tire would have spun in the opposite direction, but it didnt move and neither did the drive shaft.. so the RD is unlocked. When I am going slow and turning as hard as I can, it feels like the rear is under complete lock and I get the same jerky movement you do. If I go faster the car kinda skips, and if I really push it the rear is completely unlocked and I feel like I'm in FWD only.


I've contacted HPA about it and spoke to a tech. He believes the issue is some small debris is clogging a very fine needle in the controller that the haldex fluid is supposed to travel through. I looked at my stock Quattro controller and could see no fine needle, but nonetheless I took my car to my mechanic who also has no idea where this needle might be hiding, unless it's somewhere inside the controller itself.


I've patiently called HPA back 2 times, the tech was busy and was supposed to call back after the meeting and lunch but never did, so I sent an e-mail to Darryl. He forwarded the e-mail back to the tech and I'm waiting on a response. I'll post any info I receive from HPA if it helps you, too.

[20v master]

I have an issue with my competition controller as well. When the car is off and on a lift, if I spin the back tire the other rear tire does not spin at all. I was pretty sure the other rear tire would have spun in the opposite direction, but it didnt move and neither did the drive shaft.. so the RD is unlocked.

Yes, if the car is off, the rear diff is open and unlocked from the Haldex coupler. Not sure why you'd think it would be any other way.

[Chuckmeister87]

Here is what I got from HPA today:





You might try this, redline, or you might want to contact HPA to see what they might suggest you do. I'd suggest contacting them first before trying anything.

[RabbitGTDguy]

never a similar issue here...had stock, blue and now the competition controller as well as of last year. Does do the low speed bind.

Def. contact HPA before "blowing out" that valve (as per their instructions). Hope they'd cover it if something got "messed up" if that is their solution. And...if thats the case...that'd be a pretty "overdue" or dirty haldex unit/filter change interval that would clog it up...

Joe

[racin2redline]

i purchased the unit used off someone on here. i recieved it in a sealed ziplock with all the original red plugs in all the holes so i cant believe it was dirty i also replaced the fluid and filter at the time of installation.

[racin2redline]

i might add that today i drove the car today and the abs light did not come on when i was in the car everything functioned as it should. i believe the problem i was having was related to the abs system fault and not the haldex unit

[hanzy]

You are correct OP.

Obvously the haldex ontroller requires input from the ABS/TCS system on the vehicle.

That is how it knows that the front wheels are losing traction.

If there is a fault with the ABS/TCS your haldex system will not function properly.

Before doing anything else you need to resolve the ABS/TCS issue.

"Garbage in, garbage out"


I highly doubt it is a controller issue because as you state the light was on before install.

Goodluck!

*We perform alot of haldex services/replacements at my shop(do the service every 20k!!! You will kill the haldex unit!!!).
We have had similar problems where there is a ABS/TCS issue and the haldex does not function properly.

Goodluck.

[racin2redline]

Thank you hanzy was looking for conformation on my knowledge of haldex. Now to figure out what's wrong with abs... Think it might be a stupid wheel speed sensor because of the intermittency.

[hanzy]

Well first step is to scan for dtc's.

If you wanna come down to RI I'll do it for ya.