heavy black smoke

[c-1500dsl]

hello all
i have a 1994 6.5l td. on accel sometimes it blows heavy black smoke
sometimes the thicker the smoke a kocking noise will occur in the engine
the truck is all stock

[sixnickel]

It sounds like you have a boost problem. First thing unless the air filter new replace it. Second in the fender there is a plastic snorkel that the air filter pulls air through, yank it out throw it away it will breath better. With the engine off the lever on the waste gate should move freely. Engine running the rod should be pulled into the vacuum chamber . Check this and report back.

[grancito]

My 82 chev did that, and it was the exhaust gas return system malfunctioning, and supplying exhaust gas to the engine under acceleration. Easy fix, disconnect and plug the hose with a bolt.

[stereojoey]

my 98 seems to be doing the same thing. but everything seems to be opperating as normal. i just got my new intake system installed(pics soon its flippin sweet) and the truck has a very noticable ammount more of power. the "get up and go" is way better! but after the marine injectors and #9 i think that there is too much black smoke. i puttin in my new boost gauge this weekend so i will be able to better troubleshoot. but with the marine injectors there is gonna be more smoke right? more power from a diesel equals more smoke right?

[njdevi11]

Big black smoke usually means big power, but its a little more complicated that that. Black smoke comes from unburnt fuel in the cylinders that does not have enough air in the cylinder to burn it (kinda like what happens when you put your hand on a cup with a candle in it, the fire burns up all the oxygen until it burns itself out, even though there is enough fuel to keep it burning).

Essentially black smoke is wasted fuel, If your not looking for fuel economy or efficiency then black smoke is fine because your getting all you can out of the engine... with the air thats going into it that is. (watch the egt's though) The Sophomoric solution to this problem would be to turn the boost up until the black smoke goes away, then you are not wasting fuel anymore.

So essentially there is a balance to having a high performance engine: Put as much of the proper proportions of air and fuel into the engine as you can with out blowing it up. Usually the rule of thumb for a moderately aggressive diesel (which I think is most of our goals here) is that a little bit of black smoke under hard acceleration is what you are looking for.

[sixnickel]

Big black smoke usually means big power, but its a little more complicated that that. Black smoke comes from unburnt fuel in the cylinders that does not have enough air in the cylinder to burn it (kinda like what happens when you put your hand on a cup with a candle in it, the fire burns up all the oxygen until it burns itself out, even though there is enough fuel to keep it burning).

Essentially black smoke is wasted fuel, If your not looking for fuel economy or efficiency then black smoke is fine because your getting all you can out of the engine... with the air thats going into it that is. (watch the egt's though) The Sophomoric solution to this problem would be to turn the boost up until the black smoke goes away, then you are not wasting fuel anymore.

So essentially there is a balance to having a high performance engine: Put as much of the proper proportions of air and fuel into the engine as you can with out blowing it up. Usually the rule of thumb for a moderately aggressive diesel (which I think is most of our goals here) is that a little bit of black smoke under hard acceleration is what you are looking for.

Hey njdevi11 nice post!! I second the motion. Your learning!!!

[stereojoey]

just after i posted that last post i got a ses light so i got it checked and it was a boost sensor code. thus why i have heavy blacksmoke and i also just checked my fuel mileage and it is suffering too. thanks for the help guys im learning more and more bout this awesome truck.