for what you see in my sig, is it normal to have a puff of smoke exit the tailpipe upon initial start-up?

i know my injectors are as mild as they get over stock, and the xzt+ doesn't add a ton of fuel - but would it be enough to leave unburned fuel somewhere and have it come out as smoke upon start-up?

is this a common occurrence when adding more fuel to the engine? i started noticing it more after the xzt+ and the injector swap-out.

or is it that i may be burning oil from the crankcase? is it quite common or uncommon for these trucks to burn oil?

sometimes the smoke is white to light grey, and other times it is dark grey to almost black . . . .

i am due for an oil change in a little while here so i will keep an eye on it and see at what rate the oil level is lowering.

 

Mine does it all the time and I also put ALL my used motor oil in the fuel tank...**** I love a Cummins

 

White-gray smoke on start is normal. Cold engine snufs out fire a little quicker than warm so you get a wisp of smoke on start. To prove, on a cold morning, immediatelly after start, rev her to 2000 rpm or so. It will fog a parking lot in a second. JMHO

 

yeah, i've seen it pour out white smoke on cold morning starts too.

i would have thought nothing of this - but it seems my oil level is slowly creeping down and this is what came to mind first. where else could the oil be going?

anybody else???

 

My 2000 has done this since I bought it in '03. It seems to be normal and I don't have any oil issues. Mine does it a bit more now since I put the 4" stainless exhaust but it's still a puff and it's gone.

 

Is your vacuum pump leaking? My truck uses 1qt on each oil change and I chock that up to blowby.

 

how do i check for this?

also, just noticed it puffs out white smoke sometimes also . . .

 

Could be the fuel. If it's minimum 40 cetane rated, that will smoke a lot more on start up than say, one that's rated 47 minimum cetane. The higher the cetane rating, the better the ignition quality. Unfortunately, cetane rating isn't posted at the pumps like gasoline's octane rating.

 

My truck would always blow out smoke on start up just on initial firing than after nothing.

cold weather i would get white smoke but thats normal.

 

i have been using the same fuelling station for a long time now.

it smokes white sometimes, great sometimes, and dark grey sometimes. it has not been cold lately either. and it seems to have just started within the last couple of months - after installing the injectors and xzt+ . . .

 

I get a quick black puff when my '01 starts.
I figure that it is just waiting for some boost.
So I give it some!

Dry Creek