After many months of delay I have at last cleared this defect code from my car. I purchased 2 cam timing sensors from the dealer (about £60 for the two) and the car is now running a lot smoother and not so much power lag in low gears.
Still soundng like a diesel at idle for a petrol car but will see if that improves over time. The other problem of the air con, which could be the air con compressor (?) will have to wait for another day. I just switch off the air con and the noise goes!
Have to save up some more cash before I can pay out for the air con repairs and investigate the diesel sounds at idle.