electric speedo problem

No, I dont mean the battery powered banana hammock type speedo.....I mean the thing in the dash that says how fast I am going.

About a month ago I was heading to work and when I got to a spot in the road where the speed limit slows to 35MPH I looked down and the speedometer was reading a steady 75MPH even as I was decelerating. I did a double take and a triple take on it and tried to remember if I had been drinking that day. It was fine after that for the most part but the needle kinda sticks on the highway. Say I am doing 65 and let off of the gas, the speedo will sometimes hold 65 and then suddenly drop down to 55 or whatever actual speed I am going.

I have a '93. I was at the junkyard yesterday doing field research on this and found a '92. No speedometer cable going to the back of the speedometer. I guess I have an electric speedo. So what could be my issue here?

My speedo recently started jumping wildly! I also noticed the rev limiter was lowered to 3000rpm. All this was after a wheeling trip. Yes you have an electric speedo. On the rear of the transfer case is where it plugs in. My plug was slap full of water so I sprayed it out w/ some WD-40 and good as new. it sounds like your speedo is getting too much voltage from the sender.

So, yesterday my speedometer took the day off. It didn't work at all. But on the way home from work last night it decided to come back to life. Any way that I can test the gauge or the sending unit to narrow down the problem?

kingmeirl I unplugged my sending unit and gave it a Hollywood tune-up and suirted a littl WD-40 in there and it came back to life. Thanks. It is still jumpy though and I would like to replace the sender. I can't seem to find one anywhere though. No luck at the local junkyard. I can't find one on line either. I tried Quadratech even though I vowed never again. Any suggestions?

Now it is working one day and not the next. I assume that this is a rare problem since there are next to no posts on this. An intresting note, the odometer still turns when the speedometer is not working. Same sending unit, right? Make me think maybe the guage itself could be the culprit.

Your sending unit is probably on the blink, or (hopefully not) some wiring is intermittent...

Replacing the gage cluster should be pretty easy if you decide to - four screws holding the plastic bezel in, plus some spring clips. You'll want to remove the steering column trim and tilt the steering wheel down if you have that option. Then removing the entire cluster is another four screws and a few connectors. People here very often swap the cluster out to go from "idiot light" style indicators to actual gages. Be careful though, the odometer logic on the pre-97 models is built into the gage cluster (or on the older units, mechanical), so you will have to either get proper documentation on the swap or find a way to transfer the mileage to stay legal.

Unplug the wiring at the sender, clean it out with an aerosol electric contact cleaner, then smear it with dielectric grease.

WD-40 is very good at displacing water, but I wouldn't leave it in an electrical connection. When WD-40 dries it leaves a nasty and persistent coating. I have spent HOURS cleaning WD-40 out of firearms.

Doesn't the sender count turns though? The odometer is still rolling when the speedo doesn't work. This is what has me perplexed. Replacing the parts isn't the problem it's figuring out what to replace. And I can't find a sender anywhere.

Thanks for the help.

I thought about the dialectic grease. I'll do that.

If the odometer is turning, it isn't the sender, it's the gauge. Sounds like you need to replace the cluster...

Found a suitable replacement in the JY today. I was a bit concerned that all six guages were going to work. But they did. Problem solved.

Since I am tossing the old one out, I decided to take it apart. And I noted if you did get a cluster that had a bad guage it looks like it would be possible to replace just the speedometer section.

I had my speedometer and odometer quit working today..would my issue be the sending unit?

what year? 91? yeah, the issue is probably the vehicle speed sensor or wiring between it and the instrument cluster.

Thanks I'm going to take a look at it tomorrow...