Speedometer not working, but no dash lights on & B6's don't have VSS, but ABS?

[Surf n' Turf]

2002 B6 A4 1.8t Quattro Avant

Got back from being out of town and when I was driving back from the airport I noticed the speedometer was not working. At first it wasn't working at all. After being on the highway for a while it started bouncing around and finally sort of worked - in that it seemed to be near the speed at times, but was very sluggish at moving around. I haven't confirmed if odometer is working or not yet. I will next time I go out.

I do not have any ABS or other lights on the dash. I will note that my fuel gauge had been acting weird a couple times in the last few months. It would sometimes not read a whole tank and then fix itself. I presumed that was a sending unit going bad or being blocked in the tank, but now wonder if they may be related because I have seen other forum subjects with fuel guage and speedometer problems.

I note the B5 VSS and magnetic drive gear/wheel problem and fix (http://www.audizine.com/forum/showth...ausible-Signal), but when I called the dealer to get my VIN part numbers for the VSS, I was actually given the front ABS sensor part number and told the magnetic wheel/gear does not exist the same in the B6, but would have to replace the hub and bearings (much more expensive).

First, is this true that the B6 does not have the VSS (Vehicle Speed Sensor (I just replaced the Engine Speed Sensor a month ago))? Is it true the B6 does not have the magnetic wheel/gear that is in the diff behind the front driver's wheel?

Second, any ideas on problems and solutions?

One thought is to clean the ABS sensors, but since I'm not getting any ABS or other engine or sensor lights, I don't think that is "necessary" (but never a bad idea). Same thought process that the ABS sensor(s) are not bad.

I will add two additional bits:
1) Before I left for the holidays I did catch a curb somewhat rough with my front passenger tire (bent the outside edge of the rim and knocked some air out of the tire; and
2) I have had some grinding noise coming from what sounds like the front driver's side of the car when accelerating out of a turn (usually turning right) for about a year thus far, that we have been unable to diagnose. If there was a magnetic ring in there, I could believe it would be making a grinding noise if it was broken. We really don't think the noise is bearings as it doesn't happen often and usually only when accelerating from a stop turning right.

[seanf86]

it should, I was under the impression the 2002 models had a speed sensor on the driver side axle of the trans, I know my 2002 does and that it changed in 2003 when they started using the driver front abs sensor.

[Surf n' Turf]

it should, I was under the impression the 2002 models had a speed sensor on the driver side axle of the trans, I know my 2002 does and that it changed in 2003 when they started using the driver front abs sensor.

That's what has been confusing me. I saw that as a good fix on B5s. Then I saw some 2002 owners refer to it, but when I called the dealership looking for parts and provided them my VIN he provided me with part number 8e0927803a, which is a front ABS sensor. And then when I started asking about the magnetized wheel/gear, he was telling me that it was different and I needed all new bearings and hubs.

From the problems I'm having it seems more likely to just be VSS and the magnetized wheel/gear broken, but was confused by the dealer parts discussed above.

To update on status (because this seems wierd): Last night when I went out for errands the speedo needle was a 0 and didn't move for about 5-10 minutes. Then it started to move a little bit and around 10 minutes plus of driving the speedometer was working, but not extremely well. It was like it had to warm up to work, which did occur briefy yesterday as well. Then this morning when heading to work the speedometer worked, but not well. It does show acceleration, but does so slowly and does not adjust quickly. When the speedometer is not working the odometer is not (the trip odometer reset itself as well, if that helps), but the odometer works somewhat when speedometer is working (badly). A check engine light did just come on, but I haven't had a chance yet to run it. I have been having CEL issues with the second O2 sensor since my K04 and APR K04 software upgrade, so the CEL may not be anything with this.

Doesn't seem like a cluster or abs problem. I'm gonna get into the passenger front wheel well and make sure nothing was broke there where the curb was hit, but I don't see how something on that side could affect the speedo.

Sure seems like a Vehicle Speed Sensor (VSS) and/or magnetized wheel/gear diff problem.

[seanf86]

sounds like a vss to me, if you take the coolant res off and look straight down you'll be able to see where the driver axle attaches the vss is right there if you have one. I'm fairly certain its a cheap part.

[seanf86]

So it looks like a build date of up to june 28 02 has the vss on the driver side axle flanges.

[old guy]

Just open the hood and take a look. You will either have a VSS or a rubber plug. If you have a rubber plug as shown on my late model '03 the signal comes from the front left ABS sensor.

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[Audiguy1234]

If you don't want to deal with that sensor anymore. You can run a wire from the ABS (terminal 34) to the speedometer wire pin 5 on the IC. A bit more work than just replacing the sensor.