Hi all, I'd be very grateful if someone could advise on my daughters 2010 astra sri 1.6 ecotec it's showing codes P0011 & P0014 I've been advised a few different cures , have tested both cam sensors or oil flow sensors on the top end and both are testing as OK, both cams line up on the timing marks as should, I've checked the loom up to the sensors, someone has told me that it will be both pulleys need replacing and they're about 200 quid each, is there anything else it could be?