Snoozy Speedo

CrossT · 08-20-2007, 03:53 PM

My 86's speedometer has taken to not moving until I get to about 35mph at which ponit it wakes up at seems to operate normally. Anyone else have this? Is it a symptom of something I should maybe look at?

thx
todd
86 coupe

berettafan · 08-20-2007, 05:49 PM

mine does the same. i believe it is dirt in the line. mine also bounces at various speeds.

nameisbauer · nameisbauer's Garage

I advise to drive way over that as much as possible

4flyboy · 4flyboy's Garage

Yeah my '85 does this, surprisingly the odometer moves normally whether the speedo needle budges or not. I have no idea why. What does dirt in the line mean, I figured that it was an electrical glitch. Is there anything that I can do myself? Thanks to whomever can advise on this.

Scott

khamul02 · khamul02's Garage

Probably need to replace the speedo sender mounted on the tranny. Mine did the same. I replaced that guy (about $100) and it works like a champ now.

rick-l · 08-20-2007, 09:06 PM

Quote:

Originally Posted by 4flyboy

I have no idea why. What does dirt in the line mean,

Did you notice berettafan has a 1970 2.4? His car has a cable in a tube with a mechanical differentiator.

In 1970 you could buy nand gates, nor gates, resistors, transistors and capacitors and that was about it. A speedo would have occupied the space of a radio.

berettafan · 08-21-2007, 05:43 AM

oops, forgot you fancy modern guys might not have cables.

khamul02 · khamul02's Garage

Maybe it operates on Tubes

preston_brown · preston_brown's Garage

My 87 does this. I don't think it is the sender. If I give the speedometer a light "tap" with my finger at slower speeds, it wakes up and registers. I think it must have dirt inside or something, and when the electro-mechanical motion gets strong enough (like at about 40 mph) it overcomes the stickiness and moves.

cattledog · cattledog's Garage

Same story on my '83. A light tap on the bezel wakes it up or a small bump in the road will do it also. I know there are threads on disassembling various gauges but I haven't seen one that addresses this specific issue.

khamul02 · khamul02's Garage

Guys, Mine was doing this as well. It was very strange. A light tap would get it working but when I replaced my sender it work all of the time.

Very strange.

mtbguy · 08-21-2007, 01:02 PM

On my 87 Carrera it wakes up at 20mph. Odometer seems to be normal though.

Long Nose · 08-21-2007, 02:01 PM

My 82 VW Vanagon does the same - although I probably spend a lot more time below 30mph than you guys do...

Dan in Pasadena · Dan in Pasadena's Garage

I posted a thread on my speedo problem a while ago and got little response so I should mention it again here. My '76 speedo suddenly won't register higher than the low 50 MPH range no matter what speed I am actually going. It doesn't not act arratic up til that speed, needle movesd smoothly.

Does anyone know the cut off year between an electrical and a cable operated speedo? I think it might BE '76 is the last cable year. Is this problem more likely to be the cable or the guage and what will it cost to fix it?