407 Diesel Sluggish When Cold

Put some diesel treatment stuff in it . that helps my 405 was like that untill i put some redex in the tank and gave it a good run .so give that a good try .

i put some redex in the tank and gave it a good run .so give that a good try .

I wonder if your engine temperature sensor has gone out of spec. If it had failed totally, then a fault should have been identified but if it is in range but just telling lies ie indicating the engine is warm when it is cold , this would not happen but could explain the symptoms. I'm not familiar with the 407 engine so can't tell you where it is located.

hth

Bob

untill i put some redex in the tank and gave it a good run .so give that a= good try .

I think I have found what was causing the problem (though I don't understand why). I had booked the vehicle in (overnight so they could reproduce the problem the next morning, when sub-zero temperatures were forecast). However when next I attempted to start the vehicle - nothing! All displays were normal but no starter. Simple - a battery which had reached the end of its useful life. And, with a new battery, the morning sluggishness problem has disappeared. I wondered whether the turbo was electrical (well, radiator fans made this switch years ago! No - turbo is exhaust-driven. My best guess is that some system is voltage-sensitive - with a dicey battery, starting would drop the voltage. It would take a few minutes for the alternator to bring the voltage up, at which point things return to normal. Bob's suggestion that the temperature sensor could be involved is a possibility. I will ask the Service Manager. Any ideas??