Engine/Transmission (1994 - 1998) white smoke on cold startup

[shendren]

cold this am in columbus, 22deg F. started the truck and noticed that there was a light white smoke. i don't notice this when it's warm in florida... ... . what's up??



thanks. scott.

 

[KLockliear]

Might want to check pump timing and pump inlet fuel pressure - could be a stuck return valve.

 

[shendren]

thanks. i will check that.



my timing was set to 15. 5deg at 60k. could it have slipped?



also, curious, why would the return valve affect it only when cold?

 

[illflem]

Scott, if your truck wasn't plugged in at all or not long enough it's totally normal.

 

[Ben Rumson]

White smoke usually means that the engine is not hot enough to get a full burn/combustion of the fuel. You'll see this alot on some of the larger rigs and construction equipment first thing in the morning when it's real cold outside. Pure white plume of exhaust that fills the entire area.



Once the block heats up to normal operating temps the white smoke should go away because the fuel is properly burning.



Electronically controlled timing can adjust for the real cold temps and reduce the amount of white smoke.



If it's warm enough to not put out white smoke at start-up I may let it idle for a while before driving, but never when it's so cold that white exhaust is present. My rule of thumb is that if it's cold enough to be putting out white smoke then I insist on warming the truck up WHILE driving. Idling at these temperatures is IMO not good at all for wear and tear on the cylinders.

 

[shendren]

yep, that's what it was i guess. i hadn't noticed before because when i'm here in indiana in the winter, i plug in. last night, i didn't. this am, i got up and it wouldn't start. batteries dead. had to get 2 new ones. just went to walmart and got the "maintenance free" ones with a 9 year warranty. put em in and it didn't hesitate. thank for all of the comments... ... .

 

[WPate]

Could it be the AIC is not adjusted?

Originally posted by Ben Rumson

White smoke usually means that the engine is not hot enough to get a full burn/combustion of the fuel. You'll see this alot on some of the larger rigs and construction equipment first thing in the morning when it's real cold outside. Pure white plume of exhaust that fills the entire area.



Once the block heats up to normal operating temps the white smoke should go away because the fuel is properly burning.



Electronically controlled timing can adjust for the real cold temps and reduce the amount of white smoke.



If it's warm enough to not put out white smoke at start-up I may let it idle for a while before driving, but never when it's so cold that white exhaust is present. My rule of thumb is that if it's cold enough to be putting out white smoke then I insist on warming the truck up WHILE driving. Idling at these temperatures is IMO not good at all for wear and tear on the cylinders.