Speedometer Sometimes doesn't work

[xtmsports]

Hey guys, I have an intermittent speedometer problem.

Occasionally, the needle will stop working. After driving for a while, it will sudden start working again.

Can anybody please shed some light on this problem?

Does this mean I need to find a new speedometer or maybe WD-40 to free a stuck needle?


Thanks.

[Javier]

When needle dies, does the OBC also dies, to check, just program limit speed to actual speed, and see what you get.

Javier

[Beemr750]

Check cruise control if it fails along with speedo start looking for a speed sensor.

[Kalevera]

You could pull the speed sensor and clean it off...

But since you're going through the hassle of taking it out, might as well replace it.

best, whit

[xtmsports]

If iti is the speed sensor, where would it be located?

Thanks.


You could pull the speed sensor and clean it off...

But since you're going through the hassle of taking it out, might as well replace it.

best, whit

[Kalevera]

It's a POA to pull. Here's how I did it:

- Lift the rear of the car and put it on jackstands.
- Sensor is located on the differential. All models should be in the same area. Before you pull it, you might check the wiring. It's common for it to corrode out (and you'll be happy and lucky if this is the case).
- I *think* you'll need to drain the diff in order to pull the sensor and not get dumped on. I was changing the fluid with redline anyway when I did this procedure, so the old stuff had to come out. Prior to draining the fluid, make sure you can open the fill bolt (hehehe) and that you've got a multi purpose pump so you can put new fluid back in (use Redline).
- The hard way (how I did it):
A) Need two tools: get a small box end wrench (6 or 8...I forget what the bolts are), a lot of mini extensions (or a 1/4" drive clicker will sometimes do), and a socket (to match the box end wrench).
B) Remove the two bolts. They're a POA. It took me about 15 min. Lots of tight spaces (hence having extensions and the wrench will help you out big time).
C) Pull the old sensor. Mine was gunked up. I replaced it. When installing the new one, put some gear oil on the seal for a snug fit.
- The easy way (relatively speaking):
A) lower the diff and do b) from above in two seconds.

EDIT: And there's a writeup on all of this on Bruno's site (http://www.bmwe34.net).

Best, whit

[Javier]

below speed sensor hole, even more if rear is lifted, see location in this link.

http://www.realoem.com/bmw/showparts.do?model=HD23&mospid=47408&prod=19920100&btnr=33_0148&hg=33&fg=10

This is the Bruno's site Lowell told you about. Excelent advise there.

http://www.bmwe34.net/e34main/maintenance/electrical/speed_sensor.htm

Javier