When i am in traffic for a long time the exhaust system let out alot of white smoke i recently did a tune up and i don't know what is the problem. My car is the mitsubishi galant 2003

White smoke is an indicator of moisture. All cars will show water vapor at start up as heating up drives moisture out of the exhaust system AND the combustion of fuel produces water vapor. Until things warm up, slight white "smoke" can be seen coming from the exhaust. If there is a lot of smoke, more than a normal car starting up, that could be radiator fluid leaking into the combustion chamber. Is the radiator fluid level going down? If it is, that it could be a gasket leaking.

White smoke is usually coolant being burned thru the engine.
Blue smoke is usually oil.

Is it a lot of white smoke? White/Gray Smoke: White exhaust smoke is an indication that coolant is burning in the combustion chamber. These are possible causes:
Cylinder Head: A crack in the cylinder head (around the coolant jacket) will cause coolant to enter the combustion chamber.


Although for some cars white smoke is normal, as long as it is not super excessive.

Don't forget any water that got into the exhaust system will take a
while to burn out of the muffler,cat ,ect.
If the belt whines like a supercharger ,it's too tight.
Not sure about this
model but if it's an automatic and has a modulator valve,transmission
fluid burns white .

White exhaust smoke usually comes from coolant in the cylinders, indicating a cracked head or blown head gasket. The best test is to pressurize the cooling system, then remove the sparkplugs and look for moisture in the cylinders. Turning the engine over with the plugs out will spray a mist from any cylinder with coolant in it.

Black smoke indicates running "rich" (using excessive fuel) sounds like an injector is sticking open. I would first run a strong fuel system cleaner through it. (Maybe even have a professional fuel system cleaning) Ques? When was last tune up? A dirty air filter would contribute, but not make alot of black smoke.

Blue smoke is oil and means you have internal engine damage.
White smoke with a sweet smell means you have a blown head gasket (check antifreeze, if it's low that is another sign)
White smoke with no real smell is water in the gas tank. Grab some water remover.
Black smoke is a sign your burning to much gas, you need a tune up.

IT IS LOOKS LIKE HEAD GASKET. WHEN THE HEAD GASKET IS BAD WATER GOES INTO THE TOP OF THE ENGINE (COMBUSTION CHAMBER) AND SHOWS WHITE WATER VAPOR AT THE EXHAUST= IT NEEDS A HEAD JOB
ANOTHER OPCION IS PUT A- BLUE DEVIL- HEAD GASKET REPAIR THE SMALL BOTTLE $36.00 (FOLLOW INSTRUCCION S IN THE BOTTLE

you need to install a lower temp thermostat. and check the timing too far advanced will also cause this problem

a tune up will not cure smoke, sounds like u may need a head gasket replaced.