hi, don't know about rovers, but when I changed the timing belt on my peugeot 205 it would not start. we towed it along the road and it sort of fired and ran like a sack of nails. we stripped all the covers off again and rechecked the timing marks. the fuel pump was one notch out, and that was debateable as there was a little bit of slack in either direction. we reset it, after that it was fine. what I'm saying is if the belt was not correct I doubt if the engine would run at all. no error for margin with diesel. as you are probably aware, when you switch on from cold the pre-heaters energise for a period of time(depending how cold the engine is). these are linked together by a common wire and are found next to the injectors as the go into the engine.(usually) these heat the diesel and turn it into gas so it can combust. are yours working?or are your injectors fouled up? tip a bottle of redex in your fuel, that will clean it up, as the injectors may be dribbling when you switch off.
alf.