Seems like about once a day, and only when it's warmed up and driven awhile, then shut down, my truck doesent want to start normally on the 1st crank (if it doesn't start after 5revolutions I stop). It allways lights off real fast on the 2nd crank though. I have observed and many witnesses also have seen black smoke out the tailpipe about 2-3 seconds after firing. Just wondering if this is something to be worried about????

 

i have had it n high temp weather and also get a vibration in the truck, but after driving it again it goes away. it's been awhile since it happened to me.

 

black smoke comes from :


a bad injector( clogged)

air inlet restricted

incorrect engine timing

internal engine problem

simplest is the best- doing a lot of low heat runs? got to 3500 rpm it to burn off these newer fule mixes that will lacquer the surface of the valves. tak eit out for a good run if the black smoke increase or you know you have done some short runs where the engine cannot keep a sustained temp of 80 celcius...(185-200 degrees)

my two cents; more guys here know more

Heidi in NY

 

Wow... that's a pretty good post, DTR mom...

I would also add that it could be bad rings... right? I can't remember why, but our 92 used to shoot out black smoke on start up, and my dad said it was because a little oil was leaking onto the top of the pistons when it sits, or some baloney like that.

Run it real hard, and if it gets worse, you know you broke something...

 

bad rings=blue smoke

 

I'm starting to think it's something to do with the CP3.......Cause in an earlier post, I said the truck was sounding like an old 12v, but went away when I filled up last that made me think bad fuel. It's back and seems worse. It's definate injection pump ratlle and not injectors due to the location of noise and I can hear it in my fuel pressure gauge.

This never happens when cold starting, no loss of fuel mileage, no white or blue smoke at all, and only a puff of black on a 2nd crank attempt when it's needed. No abnormal smoke of any kind, just the bad rattle and the symptoms above.

Checked for codes with a Diablo Predator and it doesn't give #'s, but said the control module program in default/not programed. Whats that??? What control module it didn't say. I usually check codes about 1 time a month at random. Never had this before???

 

Ok, so yesterday I was doing alot of in-town driving where I had to crank the truck many times which allowed quite many opportunities to observe these problems.

1. Yesterday morning was the coldest so far this season here. Cranked right up no hesitation or bad idle until put into drive which added load. Again, no white smoke, but even at idle it was black smoking slightly and let out good puffs of black at the slightest throttle input. Cleared up and smoothed out when fully warmed up.

2. No loss of boost that I can tell to account for the back smoke, or egt probems indicating stuck/overfueling injectors. If anything, I would say the egt's are cooler than usual and the power it has now is awesome.

3. To try and describe the sound better. It sounds as if there is a good cam in the engine cause it seems to have a lope to it in the exhaust tone and when I raise the hood, you can here the way it fires thru the intake.

 

black smoke is fuel dont worry about that, got over dozon cummins in the family half over 250,000 , dont worry about the rings when they ware your smoke will be blue, and hopfully that will be a looong time, your puff of black is prob. same thing as the truck im working on, prob. injectors on both trucks either dirty,worn,leaking something we need a deal on some injectors.