I was driving my 70 el camino and went over some railroad tracks, the needle on the speedometer bounced around a few times and then totally stopped at 35 mph. Now it is just staying there, even when I'm totally stopped or at highway speeds. It is a sweep style dash, any suggestions or ideas on what to do or where to start with this?

Check the cable.
Sounds like a broken cable.

Take the cable off, Pull the cable out of the housing.
If it is good, grease it, stick it back in spin the cable to see if the speedometer moves.


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hmmm that sucks.

Really novice question here, but how do I take the cable off, and what am I looking for to see if its broken?

hmmm that sucks.

Really novice question here, but how do I take the cable off, and what am I looking for to see if its broken?

The cable unscrews at your transmission. You unscrew the housing and inside is the cable.
you can pull the cable out of the housing. if it's broke, you will see it. Also once unscrewed spin the cable with your fingers. have somebody watch your speedo to see if it moves.
Speedometer cables unscrew at the transmission. the back of the speedometer the cable either unscrews or sometimes there is a clip. you will need to be a contortionist to get under the dash. The first time you do this you'll be swearing. once you get it figured out, it is easier (but still sucks). just get out there, you'll figure it out.

Quote from the movie Water Boy, "You can do it!"



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The cable cannot be pulled out from the transmission end. It comes out from the speedometer end. Broken cable is the first thing I would check too.

The cable cannot be pulled out from the transmission end.

Yeah I was trying to remember, been a long time. That's what I was thinking.



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Update, I was driving it, and it started working again on its own, so I tightened everything up, and well lets hope thats the end of this :D