2009 cooper S. started having a longer than usual start up, slight rough idle, poor fuel economy, no low end power
actron scanner showed p0012 and p1497. i changed the vanos slolenoid and cleared the codes. p0012 did not come back but the car ran worse and started coding p1338 and still p1497. changed the camshaft position sensor, no change and still codes p1338. i cleaned the original vanos senor even though it did not look dirty at all and put it back in, no change. could not find any air leak and am running out of ideas to try. are there any other problems that can cause these symptoms? is there anything else to check the vanos system? the car runs smooth and makes some power at high rpm, nothing on the low end. i have read several other similar threads but have not had any luck. any tips or suggestions or links to more threads about this will be greatly appreciated. thank you for anyone's time that replies

 

just saw a post about a bad non return valve, could this be an issue also and if so where is it located? looks like a torx head, what size?