Jumping speedo needle w210 320 cdi

[too_juicey]

Morning all,

The speedo on my e320 cdi w210 (2001) seems to be jumping up in steps instead of being smooth. After about 50mph it jumps up as though it's notched, instead of smooth. It's fine on the way down though.

Last time this happened it was when the injectors packed up - I am not sure if it's linked, but the car has also developed a very "lumpy" idle.

Any ideas?

 

[television]

This does sound like a speed signal fault, but how this affects the engine I do not know,, rev counter yes, but speedo no.

Hopefully someone can throw some light on this,and I will see what I have this evening

 

[too_juicey]

Thanks Malcolm, obviously - any help is appreciated that avoids a visit to...dealers!