Problem starting Dodge Ram 3500 when engine is cold. I have spent $600 trying to get this fixed to no avail. Dealer adjusted engine computer, and mechanic replaced intake manifold heater. Truck still won't start in the a.m., even when outdoor temps. are 60-65 degrees, but starts perfectly after one hour with block heater plugged in. I contacted Cummins diesel manufacturer and they say the engine should start at 40 degrees cold so they say the problem is not with the engine, but with something else in the truck. Any suggestions on what to check out next would be most appreciated.