white smoke

[Momohenri]

Having really taken care when replacing the cylinder head gaskets, I am surprised that this comes from that. By cons I wonder if it could not come from a leak of coolant by the intake manifold?

 

[ExploreNW]

When you did your cylinder head gaskets, did you replace the valve seals while you had the heads out?

This is 100% guaranteed not a sensor issue. Gasoline burns gray or black if the air/fuel is too rich and it won't burn at all if air/fuel is too lean. Oil burns white or light blue. Coolant burns white & smells.

The "mud" is regular contaminant drip. Products of gasoline combustion in air are CO2, CO, NOx, SOx, Water, and Carbon (Soot). Lots of water. This is what condenses in your tailpipe and washes soot out with it.