Speedometer is out of whack!

when i turn on my car and put it in first my speedometer needle will jump to approx. 30 km/h and will stay there no matter what speed im going… It just stays at 30 and it will often jump back down to zero then start working properly. Strange… im thinkg just a sensor or something… anyone know?

Please give us a little more information, make, model, year of car, automatic or manual gear box, and any information about how and when it first occurred. Without useful information, how can we give you useful suggestions.

It’s probably the VSS (vehicle speed sensor), but Researcher is correct: more info is needed!