See Smoke

Have what appears to be grey exhaust smoke coming from the hood - any ideas.

Crack in the exhaust maniflod?
Blown exhaust manifold gasket?
In those cases it would be noisy.
Oil leaking onto the the outside of the hot exhaust manifold?
Gas or oil leaking onto the outside of the red hot turbo charger if so equipped? That will cause a FIRE. Ask me how I know…

Then too, it could be steam. Does it smell like smoke, of maple syrup? MANY car “fires” are reported to 911 when they are really just a burst radiator hose. If flames are visible, tell the dispatcher “Code 3, flames are visible”. Ask me how I know…

Did you - by chance - open the hood and look?

It is not noisy but the exhaust manifold makes sense. Allow the car to run a little and it builds up - raising the hood can see the smoke freely flowing from the back engine area towards the Driver

Opening the hood may give it just enough oxygen to start a fire…ahh i doubt its smoking THAT bad. Gray smoke…Yeah you should be able to track that visually.

Also opening the hood may give it just enough oxygen to run the engine.