when up to normal engine temp on a motorway if i meet an incline squeeze the pedal the car cuts out and the glow plug light ilumiminates on the dash board switch the engine off and re start every thing is back to normal if i meet an incline and use the gears in manual mode dont squeeze the pedal come up a gear then squeeze to get the speed to increase then dpro down a gear everthing is ok but after it happening si times on the m25 on saturday now the engine management light has come on an stayed on for the first time'has any body got any ideas

many thanks Chris