[nhraracer90]

Is a stock LB7 supposed to throw any black smoke at all?

 

[billygoat7c]

no not really, if you are real easy on it for a while and soot builds up in the pipe or whereever it does, and then stomp on it, you will get a little cloud

 

[nhraracer90]

Mine will blow black smoke everyday, it will do it when the rpms are 2500+ and about 3/4 throttle and the more throttle you give it the more it will smoke..it will throw smoke until the rpms drop. Its not a really dark black smoke, its enough so that you can see it during the daytime in your mirror. Any help is great. Thanks

 

[yellowroket]

have you had it since new? Previous owner could have flashed a small tune into it? I had an intercooler pipe come loose when mine was bone stock and it would throw black smoke cause it was loosing boost maybe start checking there.

 

[Kawtipping]

Just what every LB7 owner wants to hear...Perhaps an injector going bad? Do you notice a lack of power? If so, it could be a low boost problem. Smoke on start-up, or fuel smell in the engine oil?

 

[nhraracer90]

No smoke on startup. I have not owned the truck since new, but when I bought it, it did not smoke. It blows more smoke when its cold. It doesnt just puff smoke once, it keeps smoking until the rpms drop down or i let off the throttle.

 

[yellowroket]

i didnt want to freak him out with the whole injector deal just yet, but from what you say i would probably take it to gm and have the balance rates checked! Atleast if its not the problem you will know. My last set that went out i noticed that the smoke seemed to be lighter than normal and go figure took it in and ended up with 8 new ones.

 

[nhraracer90]

ok..ill try to get it to the dealer and get it checked soon

 

[jugdish35]

Mine never smoked with the stock tune...

 

[nhraracer90]

Auctully when I started mine up on a cold start today, it puffed some black smoke when it fired. What does that mean?

 

[duramaxguy04]

I can lay a trail of black smoke if I put the hammer down. Bought the truck with 4 miles on it and it is 100% stock. Unless I hammer down I never see any smoke.

 

[nhraracer90]

I was just wondering becuase it never smoked when I got it and now it is. I just dont want anything to be wrong.

 

[WanaDmxsub]

Air filter clean?
IIRC (it's been a long time...)Mine never smoked when stock.