99 Buick Lasabre Spedo

**Andrew Rhone** · 12-09-2011, 07:47 PM

If I can get some help from the Hot Rod family, I have a 99 buick lasabre that has a bad speedometer in the dash (I can be going 30 (according to my GPS) and it shows anywhere between 0-100 sometimes going back and forth. I am sure it is just the spedometer because the cruse control still works when I bump it up 1mph it does as told. I don't want to rip apart the whole dash to replace a $800 part that has been replaces profesonally before. I was wondering if I could get a aftermarket spedometer and mount it to the hood or dash withougt any problems, I would also need to know what to wire into if it is at all possible

**Century** · 12-11-2011, 07:47 PM

Have you tried drying out the speedo cable. and the head as well?

**Andrew Rhone** · 12-21-2011, 03:13 PM

Originally Posted by Century

Have you tried drying out the speedo cable. and the head as well?

Would letting it sit in a dry garauge for 2 weeks count to get the moisture out? if not how would I do that, would I have to remove the dash, find the wire and take a hairdryer to it? Also would moisture make it do this constantly for multiple years? Also what do you mean by head?

**Century** · 12-21-2011, 08:14 PM

Not moisture. Speedo cable at transmission. The seal quits allowing transmission fluid to climb the cable eventually working to the head.
Try disconnecting at the tranny , pull the cable core out of the shieldingslightly to see if there is fluid on the cable. If so remove cable dry with a cloth and reinstall. This usually
gets the cable running smoothly and then the head corrects itself. Otherwise you have to pull apart the dash and clen the head of the speedo.
Forget all of the above I just realized you probably have a newer style digital speedo.
This means the speed sensor relays eletrically from the transmission. I really don't have any experience with that style. Sorry.

**bobc455** · 12-22-2011, 04:11 AM

Andrew, pretty sure that is a completely electronic circuit. You'd have to be willing to get into the wiring and computers.

On the other hand, adding a scangauge would give you an indication of MPH since that number comes from the computer. Look at http://www.scangauge.com/ . It also has a lot of other nifty features, and is very popular in the gas-savings community since it gives you an instantaneous MPG readout.

(I don't own one, and I know they have a few different models, so just check to make sure that the one you purchase has MPH readout. But I would guess that they all do...)

-Bob C.

**bobc455** · 12-22-2011, 04:27 AM

And just as a sanity check, make sure you didn't press some kind of "metric" button (although I don't think the '99 LeSabre has one)

**Andrew Rhone** · 02-05-2012, 08:49 PM

Originally Posted by bobc455

And just as a sanity check, make sure you didn't press some kind of "metric" button (although I don't think the '99 LeSabre has one)

I am sure I didn't I don't think it has one and I will look into scan gauge. does anyone know if it is hard to get into the dash board? I know my local junkyard has a few lasabres, may just try replacing it that way if it isn't too hard