SCREECH SCREECH and the speedo bounces and then back to normal…...

[nullset]

I'm driving, and start hearing a loud scraping sound from the driver side front wheel well, and my speedometer starts bouncing and going crazy.

A few minutes later it's back to normal.

Is this a sign of a bad angle drive, or something else in the chain between the angle drive and the speedometer?

Who has the best (most reliable) replacement unit right now?

--buddy

[sean]

Id pull that front wheel and inspect. The angle drive is not beefy enough to make a noise that you'd here while driving.

[dmc6960]

The LAMBDA counter can make the noise your describing. The bouncing could be the counter hanging up during the "screech" and the natural spring in the lower cable takes up the twist until it exceeds the threshold to get the counter moving again. If that is indeed what it is, it would eventually accelerate wear on the lower cable, angle drive, and dustcap.

[David T]

The scraping noise *could* be the dust cap spinning. It is supposed to be captured tightly between the hub and the rim of the wheel when you mount the tire. You really do have to lift the car and spin the tire while you look for the area of the noise. Could be the cable hitting the side of the tire. Could be the angle drive dying. Could be (very unlikely) the Lambda counter. If it is the dust cap, a wrap of electrical tape around the circumference should keep it from spinning. It could mean the angle drive (or the cable) needs lubrication because it is "locking up" and getting difficult to turn making the dust cap spin.
David Teitelbaum

[dmc6960]

The scraping noise *could* be the dust cap spinning. It is supposed to be captured tightly between the hub and the rim of the wheel when you mount the tire. You really do have to lift the car and spin the tire while you look for the area of the noise. Could be the cable hitting the side of the tire. Could be the angle drive dying. Could be (very unlikely) the Lambda counter. If it is the dust cap, a wrap of electrical tape around the circumference should keep it from spinning. It could mean the angle drive (or the cable) needs lubrication because it is "locking up" and getting difficult to turn making the dust cap spin.
David Teitelbaum

I'm sorry Dave but I'm going to have to disagree with you here. There is not a chance in ____ that you are going to be able to *hear* the dustcap spinning while driving at speed inside the car. Just not happening. I would not consider a LAMBDA counter failure unlikely, my 100,000+ mile car has gone through two of them (granted the second one was used with unknown miles on it). The fact that you heard something while driving the car points to something inside the car. The other parts just cannot produce enough sound to hear over road noise and then make it inside the car. The problem is either is the LAMBDA counter, speedometer head, or cables. My money's on the counter.

[David T]

I agree it is a long shot to hear the dust cap but it is as good as any place to start. The original poster seemed to be pretty clear about hearing a screeching noise from the left front wheel well, NOT inside the car. I also agree it is very hard to know just where ANY noise is coming from. When I see a problem with the speedometer, it is good to just check the whole system from the wheel to the dust cap, spindle, angle drive, cables, etc. I don't consider the Lambda counter high on the list of probabilities, they do not seem to fail very commonly (except in your case).
David Teitelbaum

[nullset]

I agree it is a long shot to hear the dust cap but it is as good as any place to start. The original poster seemed to be pretty clear about hearing a screeching noise from the left front wheel well, NOT inside the car. I also agree it is very hard to know just where ANY noise is coming from. When I see a problem with the speedometer, it is good to just check the whole system from the wheel to the dust cap, spindle, angle drive, cables, etc. I don't consider the Lambda counter high on the list of probabilities, they do not seem to fail very commonly (except in your case).
David Teitelbaum

I was inside the car, doing about 50-60mph, when I started hearing the noise. To be honest, at first I thought it was coming from the door, or forward of that. If it happens again I'll grab my camera and try to record the sound.

It was definitely high pitched, almost like white noise, or metal on metal scraping.

It was definitely audible. My passenger even heard it. It wasn't "loud", but it did start to hurt my ears after a few minutes, then it mysteriously went away.

--buddy

[D Knight]

I would point to the lambda counter. Not a bad idea to check the whole system though.