2000 Sentra code p1140

[DT]

I have a 2000 Nissan Sentra 1.8, code p1140 is set, the engine loses power and hesitates and boggs down under heavy accelaration, I know this is a valve timing sensor but is this a common symptom when this code is set, and what do I need to look for as far as visual with the sensor, is it located in the timing cover and where at.