Hi my almera 1.5saloon 53plate petrol has a problem I have just had timing chain replaced about 12 months ago and just changed the cam and crank shaft sensors 7 days ago as the car was misfiring and was not starting but when the car is cold it still wont start what I have to do everyday is put the old camshaft sensor in and the car will start but not run very well but once its running I put the new one in and it runs fine and runs fine all day long even if I leave the car turned off for 6 hours and come back out it starts but its just first thing in the morning I have to do this where I put the old sensor in to get the car running can someone explain why this happens. the cam shaft and crank shaft sensors have exactly the same part number.