Hello, The engine will not start if the camshaft position sensor is faulty. Other possible causes are insufficient rail pressure due to faulty pressure regulator, quantity control valve or injectors I suggest to have them checked with Star Diagnosis to localize the cause. Some independent MB workshops have this tool besides the dealers
Your van has an electric pre-delivery fuel pump, so the low-pressure supply is not likely to cause such problems.
Thank you Stan,
All these checks have already been done. As I pointed out earlier, it only seems to happen when there is a heavy mist overnight, and once we finally get it going, it will run all day, stopping and starting. So my question again is (CAN DAMP IN ONE OF THE SENSORS BE THE CAUSE?)