EML On

[Jez105]

My phase 2, 53 plate 1.5 petrol N16 is throwing up 2 codes P0171 and P0340 my mate says that both codes indicate that bank 1 is running to lean. Is he correct? and if so what do I need to replace as the MOT is due next week and I don't want the car to fail on emissions.
Any help would be greatly appreciated. The car has full service history and has 72000 miles on the clock, oh and the car starts and runs.
Thanks in advance

 

[Spook]

Timing chain stretch would be my guess. You can change the cam sensor first to see if that cures it though.
If you take the timing chain cover off there is the chain tensioner. If that is extended more than 10mm then it likely that the chain has stretched and need replacing.