General HELP! My speedo shows the incorrect Speed

[fiat97]

I recently bought a fiat Punto Abarth 2002 and the speedometer reads roughly 40kmh under the actual speed so say if im driving at 50khm it shows that im going 10kmh please help.

 

[flisko]

abs or not? could be speed sensor

 

[fiat97]

yea sorry forgot to add it is abs

 

[digger58]

Have rims or tyre sizes been changed from the originals? That seems to be a huge discrepancy in speed, does it register at all when you move off?

 

[fiat97]

Have rims or tyre sizes been changed from the originals? That seems to be a huge discrepancy in speed, does it register at all when you move off?

no they havent been changed. yea it registers but the speedo needle starts way below zero then starts increasing as i move faster.

 

[judderbar]

no they havent been changed. yea it registers but the speedo needle starts way below zero then starts increasing as i move faster.

I am guessing there is a balance spring for the dial which has broken or come undone so the needle is too heavy. Given the way things are made these days you probably need a new dial/instrument panel.

On my 2004 mk2b the dial begins 3mm under the zero mark and gently rises to zero when the ignition is turned on and gently sinks when it is off.

 

[Ziggy122]

We've had random needles dropping on people's car, its rare but does happen

If you go into the Punto Guides section, you'll see somebody does something very similar with a fuel guage
Its essentially the same process

And since the dash is possibly already toast - i'd be very much inclined to get the dash out and reset the speedo needle to zero at zero

Ziggy