I think I found a workaround this morning.  I start the Q400 ready to taxi, so engines are running. Smoke effects and immersion work. I shut engines down, and then save that as a default flight.  Then I launch the default flight, engines are off, but I get the smoke when starting engines from Immersion, and once engines are started manually, all smoke effects and immersion work. 

After playing around with the smoke effects -Q400-Immersion, I could not get any consistent result, so I decided to forgo the smoke effects, and actually in cockpit, the main effects I see anyway are the lighting effects which always work.  

On 11/21/2017 at 7:08 PM, Sigma1958 said:

I have contacted MJF about this and they will look at it.

I have also tested different startup scenarios and found one that works every time I have tested it .

Just start P3D select your airport etc.. select the Q400 version you want to use and load the scenario.

Then when it's loaded make the plane Cold and Dark : turn of all power also ground power, external power sw. generator sw. etc.., off with ignition and condition levers to CUT.

Save this Scenario and restart P3D
On the startup screen load the saved scenario when it's loaded you might see the external power generator wait for it to go away, if it's still there after a few seconds then you have forgot the external power sw. (turn it of save and try again).
Now you can do a Cold and Dark startup.

Regards Widar

 

PS. I still miss some effects !!!     

 

 

After trying a bunch of scenarios with mixed results, I tried your suggestion today, and it works every time. Thanks. 

Edited December 31, 20187 yr by Bobsk8