Rattle on start & Error P0391 Cam Shaft Sensor

[irelandbuyer]

All,

Wondering if this has happened here before.

Car was rattling on cold last week, was OK when it warmed up. Nothing else for the rest of the day.

The following day, the Emmissions Light came on so I brought it to my local independent who ran a diagnostic and it threw up the following fault:

"Fault Code: P0391/Cam Shaft POS Sensor.Bank 2"

We're going to swop this to the other side and see if the problem follows it and if so, then replace the sensor. Hopefully it's just a sensor but the concern of the technician is that this is actually a deeper issue with the timing chain and he feels it's an early warning that something else is amiss..

I read elsewhere that you can see from the readings if the timing chain is elongated?

Wondering if anybody has heard of this fault code etc?

Cheers.....