witwer4444

AudiWorld,

Well, I am getting frustrated guys. Before I start, heres everything I know and what I am confused about. I can post the several threads I have started on Audizine but thatd be irrelevant. I'll just start fresh with you guys since I am hoping the experts are over on here.

Little History. Bought my Mint Condition Nogaro 2001 (early 01) S4 last August in Tampa Florida. 6 Speed, 92,000 miles, Sport Package, all the goods. It now has about 100,5XX as it in storage most of the year. When the car was brand new, before the original owner even picked it up, he installed H&R Springs onto the factory struts and 18" Rims on 225/40 Tires. Fast forward 9 years to when I picked it up. The car was SLAMMED because the stock struts were blown due to 9 years and 90,000 miles of being lowered.

On start, I bought the car with the understanding that it had a minor ESP issue. The previous owner said that when the car would be at a bank on the hwy at higher speeds, (both left and right), the ESP light would flash and the car would jolt due to the ESP sending incorrect signals to the brakes causing them to do "ESP Magic." I think you all know what I mean when I say this...basically the ESP just kicks on and its annoying because it flutters. (you get the point)

I drove it home from Tampa to Michigan (1200 miles) and noticed the issue during the drive. It wouldn't always do it, just mostly at severe banks (on and off ramps especially). Wasnt too bad but I was just so happy to have bought such a clean Nogaro I didnt care at the time haha.

After doing some research when I got home, only advice I got was a bad wheel speed sensor. At the time I didnt have access to a VAG COM so I wasnt sure what codes the car had and if the wheel speed sensors werent functioning properly. I also immediately replaced the suspension with all new rims, tires, and H&R Coilovers. Lifted the car a little bit and got it to the where I wanted it. The issue still didnt go away.

Fast forward to January of 2011. Car had been in storage for the most part since September. Purchased a B6 S4 Steering Wheel and Airbag for the car as that was on my mod list from the beginning. Wasnt worried with the installation as several guys on Audizine had installed it fine. I also purchased a VAG-COM at this time to help with the wheel installation. At the time, the car scanned:

00778 - Steering Angle Sensor (G85)
37-10 - Faulty - Intermittent

After three months of figuring out all the installation bull**** (which took WAY too long to figure out), one day all the lights went away (ABS/ESP/BRAKE) when I performed a Steering Angle recalibration test. This was in April. The car scanned no ABS codes. This was a very happy day for me. However, soon after this, I found out the highway ESP issue didnt go away.

Now that I have been daily driving the car since then, the problem gets worse and worse every day. As of tonight, the car still reads

00778 - Steering Angle Sensor (G85)
27-10 Implausible Signal - Intermittent

To emphasis how its gotten worse, the ABS light wont go on until the car drives in a somewhat straight line for an extended period of time. What I mean is that driving around town it wont usually go on because the ABS/ESP doesnt get a long enough time to read a signal, so I believe. On the highway, this isnt true because you are going faster and straighter and it gives the ABS more accurate values to cause it to throw the light.

Also, whats even worse is that a few times a day I'll get the ESP to randomly kick in even if I am NOT on a high speed bank. Sometimes just turning in a parking lot will throw it and jerk the car.

Now, every time I get in the car I turn the ESP off because I am scared of it doing its weird things its been doing. This bothers me as I just want an S4 that has a functional ABS and ESP system.

Here is what is on my mind and what I am confused about:

1. Wheel Speed Sensors all read correct values at correct speeds, so I dont think any of them is bad unless they randomly send a bad signal at random times causing the ABS light to turn on.

2. When straight, the steering angle sensor reads -17.5 degrees. This is what I am confused about how the steering angle sensore recalibration test works. Does it 0 out whatever value its reading if its off OR does it just tell the car that -17.5 degrees is straight? If it should 0 out, then mines not doing so.

3. I am running 10mm spacers on my 225/40/18ZR wheels but I dont think that would cause it. Also, would a bad wheel bearing cause this? I dont have one but I one may be on its way out (no symptoms yet)

4. What is the difference between a Fault Code with a number 27-00, 27-10, 37-00, or 37-10, because I have had all 4 of those within the last couple of months all with the same 00778 implausible signal code.

5. Either my ABS is failing OR my steering wheel angle sensor is faulty. It is VERY expensive to replace either of these and I will only do so if I have a for sure answer if they are faulty. At this, point I dont think they are, I just think something else is acting up.

6. Someone mentioned that there is an ESP module under the rear seat, the one that senses if the car is about to slip to the right or left. Is this true and if so, could this be the cause? Dont really have anything to say about this as I dont know anything about it....

By the way, the car drives straight and fine. I have yet to have an alignment since I purchased the car but I dont want to until I have ALL of my Suspension/Wheel/ABS issues fixed.

My thoughts on what will fix all of these side symptoms? Find the source of the cause of the high speed ESP issue and all of this will go away hopefully. I am 99.9% sure it has nothing to do with the B6 Steering Wheel because the problem existed before I installed it.

Last thing I want to do is take the car to the dealer because theyll either tell me its because I have a B6 Steering Wheel OR that my steering angle sensor is faulty and make me pay $600. Plus, they wont even show me what they did to diagnose it all and I'll still have to pay them to do so.

This is all I can think of for now, if you have specific questions just post them and I'll answer them. When referring to any of my 6 questions above, please also put the question number so I know what you are referring to haha. Also, please only constructive comments. Last thing I need are worthless comments as you all know how frustrated this may be for me.

Thanks again in advance guys!

NefMoto

Make sure to follow the steering angle recalibration instructions on the Ross-Tech VAG-COM website.

When the steering angle sensor is calibrated, it should read zero when driving in a straight line.

It is possible that steering angle sensor needs to be replaced.

witwer4444

Is the clock spring the same thing as the steering angle sensor (G85)?

And I have recalibrated several times in the past few months..

witwer4444

bump?

Chris's S4

it's the same thing, angle, signal cancel, and esp function are all together within that one ring.

Sorry I would've posted something earlier but I've been on vacation....

If you've re-calibrated it several times already, that would lead me to believe something else is failing by not holding the zero angle. Either the clock spring/ring is going bad or esp yaw indicator is failing. I could be wrong but I'd check both those items by testing. since you've re-calibrated the spring before, then you know where to look for the angle measure. What you wanna do is turn the wheel slowly from locked one side to the other side locked... the idea is to check if the degrees jump greatly during the process. If so, then the sensor is bad/cracked. If it's a carbon system (which nowa days it is) then the carbon has either worn out or is cracked and causes a misread to the esp system thinking the car is turning and the yaw sensor is reading otherwise.. thus pisses the modules off just a little.

Also you may want to check you rear..better yet check em all.. check all wheel speed sensors and make sure there's no rust on them or inside the wheel hub. That has caused my issues which are very similar to your symptoms. Doesn't hurt to check them out... chances are, the rear ones are rusted... clean them, clean out the hub best you can... then run the car and see what happens. My issue would activate the rear brakes suddenly... like I was stabbing my brakes. Looked bad driving down the street trying to stop the car smoothly... whats smooth... nah.. lets just slam on the brakes randomly... forehead..meet steering wheel, steering wheel meet my innocent forehead...WHAM!.... not that it actually happened but still none the less... much annoying!

Good luck, let me know how it goes,
Chris

witwer4444

Chris

Best response I've gotten yet. Thanks so much. That sounds like it may be it. About a month ago I got a yaw rate sensor code a few times but it hasnt gotten back. And the car originally just kicked the esp in on BANKS aka which is yaw (Now its gotten worse)

And all last weekend I tore the wheel off and spent a while watching the angle via VAG. Did seem like it may have jumped quickly in value but I dont know what to compare it too as far as whats good and whats bad. I tried to hook up my VAG to my buddies 2000 S4 but believe it or not you cant get a sensor reading from a 2000 I guess (doesnt have ESP)

And where are the wheel speed sensors exactly?

So, starting to look like I should replace my clock spring. Scotty@Advanced quoted me $370. Maybe find a used one?

Chris's S4

Don't worry about the clock spring just yet... plus.. thats a ridiculous price. Look for one used... low mileage. My S4 has 160k and zero issues with the clock spring sensor.

I'll run a test later this evening. Sorry ya gotta wait all day to find out. Actually I can run it on my bros A4 since I'll be at work with it all day. (I work far away)

As for the wheel speed sensors, when you remove the wheel, the sensor is literally right in front facing forward on the wheel hub. It's got a 1/4 wire going to it and has a round looking head on it with an eyelet for the bolt that secures it to the wheel hub.

Once you locate it... remove the bolt, then pull straight out.. if twisting helps then do so. Do NOT grab it from the wire. The fronts maybe totally fine and slide nicely. The rears however... may not. Mine were very very unhappy campers. the left rear took over 45 mins alone with twisting and pulling at the same time very carefully with a pair of channel lock pliers/pipe pliers. With extreme care when doing it.. I started with the right rear and moved on to the left.. finished it and had to come back to the pita right side... No joke over an 1 hr and a half for just the right side.... That's how much rust has caked on, in between the walls and the sensor pressing it and keeping it from rotating and coming out. Once out, the sensor was fine, but there was tons and tons of rust flakes within the hub it self. I manage to get most of it, but the axle should be removed completely from the hub to do the job correctly (in my opinion). I pulled out some thick chunks of rust and my problem went away.. temporarily. the issue with stabbing the brakes would show up once in a great while.. Thats because I havent had the time to pull out the axles and clean the sensor rings and hub completely.. So there's little bits of rust floating around sometimes.

It's ok, just as long as your car goes back to normal. I currently work far away, so by the time I get home at 7pm.. it's to late to do much of anything. I would check the wheel sensors and go from there.

sounds to me that's contributing to your problem if not completely the whole problem along with maybe a faulty yaw sensor.

Good luck,
Chris

witwer4444

Chris

Let me know. Dont know if I can get it on a lift soon to check the speed sensors but they all read fine. Let me know how the test with the A4 or your S4 goes.

Thanks again

Dave

Chris's S4

I'm sorry, been busy at work and couldnt get away to run the test on the A4, so I just did it on my S4 and I got both +/- 505 degrees. I did notice the rate at which the degrees counted was 2.5... I think I may have seen 2.0 degrees.. but don't hold me to it.

as for the wheels sensors, it's much easier to check them with the car on jack stands, but if ya know someone with a lift, then by all means do that. How do you know they read fine? I've never looked at a reading so I wouldnt know. I'm guessing from vag-com... possibly logging? well Id hope... lol ur that guy driving around not looking at the bloody road!!! lol

anyways let me know how it goes..

Chris

witwer4444

Chris

When turning the wheel, did the value go positive to the right and negative to the left? Because mine is the opposite. And I will check for farthest values (+/-505). Mine Should read like -520 and +490.

And yes, you can read all WSS values via VAG. In Adv Meas Values (Where you read steering wheel angle above, there are 4 readings for each Wheel Speed Sensor).

Looks like I need an alignment, a used clock spring, and clean my WSS's...and see if that helps.