Hi everyone I have a 2009 focus ST 2 which iv owned from new the car has covered just 30k miles, just recently the engine management light has come on using my dreamscience handset iv read the fault code p0240, I then took it to an approved ford repairer the same place that does my servicing they said the oil filter housing needs replacing as the cills are gone and it's been creating a vacuum in the engine and are weak point on the car, so they replaced it and reset the light. 200 miles later light is back on and it's the same code again, iv been looked online and it seems like it could be the maf sensor?!

Any ideas people?
THANKS

 

Check the hose that goes from the filter housing, up behind the inlet manifold and into the top of the cam cover. Some are plastic and the corrugated section is prone to splitting. It's very easy to break when changing the filter housing. There is a updated part that is a rubber hose instead.

 

If it's not as RichieST says, p0240 is a boost pressure sensor code (MAP sensor)