Car let me down today for the first time in 3 years.... 56 plate 2.2 TDCi Mondeo Titanium X Had driven 1 mile in the cold from home with all electrics on inc seats etc, then parked for 10 mins with only ignition on but seats still on. After 10 mins tried to start it but it would only turn over and not start. Thought it was battery related so put jumper cables on it for 30 mins from another car bit still same, occasioannly turning over more and almost catching but not quite. Got RAC out and after checking correct fuel type, enough fuel, connecting a laptop to diagnostic connector under steering column said everything was OK and no fault found from the diagnostic. After taking engine cover off I was turning over the engine while he wiggled cables and when he touched the connector which connects to the sensor on the end of the injector rail the car started. It turned over a bit rough and lots of smoke out the back. He said he thought it was due to pressure sensor on the injector rail and could be the sensor or cable broken. I managed to get it home and switched off and tried to start again but same happened. On the way home some smoke from the back but seemed reasonable performance, but mpg was only about 12-13mpg on the trip computer. Tried wiggling the cable myself, took off the connetor and cleaed it and the end of the sensor but still the same. Could it be this sensor on the rail, or the cable/connector? Cheers.