If it is smoking, it isn't the CPS. It is easy to check by watching the tachometer while cranking it over. If the tach moves, the cps is good.
I am on my second 7.3 Powerstroke, and have to agree with everyone that is saying glow plugs. That is how these things act with weak or bad glow plugs. He got bent over spending $500 on a $50 dollar relay, but may have had other things done or checked while it was in for that. It is easier to ohm the glow plugs than use a wire to look for sparks, using an ohm meter will check the plug in the valve cover gasket, and the wiring under the valve cover.
Speaking of valve covers, most here probably do not know how much it takes to remove the passenger side valve cover.
If he has access to power, plug in the block heater, that will warm up the engine enough to start with even without glow plugs. If it won't start then, I would blame compression.