Hello I have a 2008 2.0 CRD Patriot, manual transmission. The car does exactly the job I need and a nice drive when running right. 3 week ago I had the engine light come.. P0101.. MAF performance. Whilst driving the car hiccups and stammer’s and then drives somewhat normal and then does it again. Doesnt have to be accerating, just a constant throttle can do it. The engine light doesnt come on until coasting downhill. I have : Removed and cleaned the MAF sensor. Removed and cleaned the egr valve Removed and cleaned the throttle body Found small bore vacuum pipe off towards the bottom front of the engine not on Checked pipe from throttle body down front of engine-- all clips intact All rebuilt and code cleared but symptoms stiil there. Now get ( whether it was before but just started to notice ) an inconsistant plume of smoke whilst on the test drive. Have read about removing the MAF plug and test driving. Have done this and it drives without a hicupp or stammer. Not sure what this means??