I just picked up my 2007 s40 after dealer first replaced oil filter housing and cam belt and cam seals then after the CEL came on shortly after repairs they replaced the sensor and shortly after the CEL is back on any idea what they are missing

 

Is it the same code as before? If so, I'd make sure they actually replaced the sensor. Many a shop has claimed replacement when they actually did not. I ask for the old part anytime they replace something.

If they actually replaced the sensor then I'd have them connect up the diagnostics to see if the timing belt is off a tooth or they moved the CVVT hub when they replaced the seals. If the cam timing is off they can tell how far. You and I don't have the equipment to do this. And you should not pay for it either.