Hi, iv got low oil pressure light on start up only, could this be the pressure sensor or would it come on whilst driving aswell, im changing pick up pipe at weekeng along with the filter and putting the recommended quantum longlife 5w30 in. Whilst im at it didnt no if worth changing the sensor?

if the sensor goes then the light will be on all the time, not just at startup. The pickup pipe should always be the first thing replaced as its the most common cause of low oil pressure at startup because the car struggles to pull enough oil from the sump. Also just because the light goes out does not mean the engine has enough pressure, merely that there is pressure at the sensor, things like the turbo for example that are after the sensor may not have enough pressure.