I have a 2008 2.0l CRD patriot. Last week the car started to "hiccup " when I accelerated and a cloud of brown/grey smoke was pumped out of the exhaust. Checked the engine and I discovered that a small hose which attaches to the air filter box was not attached ( I assume this happened at its last service two months earlier) I reattached this but it made no difference. Last night I checked the air filter and mass air sensor which look clean but the air after the mass air sensor looked like it had oil deposits on the sides (dry residue ). I also added some fuel clearer to the fuel tank. This appear to stop most of the "hiccup" but smoke was still appearing after the engine was reved. The journey to work this morning however presented another issue the cars was not as responsive and lacked power. Has anyone got any ideas. The car has 50k on the clock, it doesn't appear to be losing oil or water and it starts first time. There are no warning light illuminated on the dash.