What is wrong with my Ford Focus' speed sensor?

I have strange problem with my Ford Focus MK1 1.8-litre. When the speed sensor is plugged in my car's revs will not drop to idle when in neutral and the car is moving. In fact, when it's moving at any speed and I select neutral my rev's will start to climb up and rev the engine until I press the clutch or come to a full stop. When it's in any gear and I want to brake with the engine it will NOT slow me down, it just keep its revs or starts to accelerate. Dash trick I have code DTC 262 - U1262 - but no codes on my scanning tool. I unplugged the speed sensor and it is all fine but I have no speed and no mileage counter. I have also replaced ICV, cleaned the throttle body and intake manifold, cleaned MAF and used EGR cleaner too.
Given all that you have done so far, we would double check all air/vacuum pipes/connections for splits etc, especially the vacuum pipe under the inlet manifold Then check the TPS (throttle position sensor). When you replaced the VSS did you also check the wiring/connections as well?
Answered by Alan Ross on

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