Just done some more checks....
When the engine is off, if i take the positive probe and put it in the middle cable i get 0v. With the engine running and idling a get a voltage of about 1.84v which when the engine is revved up to about 2.5k then it goes up to about 2.5v. So it looks like the sensor is working, but if the voltage supply to it is too low, then could this be causing it to give an incorrect reading to the ECU which in turn defaults to 255kpa?
Lizzie
3 volts don't sound enough does this rise when unplugged or stay the same also how many volts at the temp sensor
if the voltage on the line is dropping under load only then there might be resistance in the line somewhere or the sensor could be doing it
it seems like the sensor is working but remember just cos it's ising and fauling don't mean it is doing it within the correct peramiters