I have trouble with my speedometer. It is working but it is showing greater speed than the real is. At low speed <to around 20> it is off by at least 8 mp/h. But when I am doing 80 mp/h the real speed is pretty much same. Do you guys have any clue where to begin with locating the problem? I got 89 W124 250D. Thanks

 

Do you have non-standard rim and tiresize?

 

Nope I got all standard tires 195/65 R15 same as wheels. Thanks tho

 

sorry, thats really all I've got lol

 

If you look, our speedo's start off at 10 MPH.

I say dont worry about it, they probly are all the same...

 

clean your abs rings.

quite a few cars use a non driven wheels abs sensor as the speedo pickup

 

Normally this could be a problem, but he said the difference between displayed and actual speeds decreases as he gets faster. This is the opposite of what would happen with most usual problems with a speedometer.

Honestly Im pretty sure its just the fact that I stated before. At a stop, our pin rests at 10 MPH on the gauge. The difference is corrected proportionally up to 20 and from there should be accurate.

 

thank you guys
first of all, i will definitely check my abs sensors... sometimes ABS light blinks on, so it might be a cause, too. i didn't know that abs sensor are used as the speedo pickup! I thought that speedometer think is build in the right rear wheel. I will spin my rear wheels tomorrow and check for result whether speed will increase. This might be a solution.
As I sad, speed is quite off until 80 MPH when actual = displayed. The trouble is when I see cops measuring speed of 25MPH. Than I am not sure, at what displayed speed I supposed to drive. So I prefer to be even slower than 25 and not to get ticket... That's why I would love to fix it.