fuel heater resolve found
 

with my 2001 smoking at below 40 degrees ad after testing air heater and fuel heater , test results showed problem was with sensor / element of fuel heater , with finding out there was no factory replacement decided to dig further to find fault, problem was an open circuit in wiring inside sensor housing, a quick solder job and testing of sensor and was working again.

Glad to hear you were able to get everything working properly. :tu:

wherer are you locate, sounds like quite the truck

Near Red Deer, Alberta

to far, anyways thanks