i have white smoke coming out the tailpipe when i start my truck
It must be steam, moisture, new trucks don’t smoke.
It’s most likely normal. Gasoline explodes by this chemical eqn: O2 + CH (i.e. air + gasoline) = H20 + CO2. The H20 is water vapor, and when it condenses into droplets inside a cold exhaust system is what is probably causing the white smoke coming out of the exhaust pipe. You may as well see some liquid water dripping out the tailpipe at first. As the exhaust system heats up the water vapor remains in vapor form and therefore invisible, but it is still there, just can’t see it.
It’s not smoke; it’s water vapor.
For every gallon of gasoline burned you produce one gallon of water.
When cold the exhaust system acts like a CONDENSER, and produces the visible vapor. As stated, you may also see droplets of water coming out of the exhaust pipe.
When the engine is fully warmed up you should not see any visible white vapor; if you do you are leaking coolant into the engine, indicating a head gasket breech or a cracked engine block.
Sooooo, white vapor when the engine is still cold is NORMAL.