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Discussion Starter #1
Hey guys... I was wondering. I've had my L-Tuned exhaust for awhile, but every once in awhile, and I'm not sure what causes it, if I step on the gas to rev the engine (so others can hear the exhaust note), in the higher rpm's you will see the slightest little bit of black spit out of the exhaust. Other days, this doesn't happen. What is it???
 

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Discussion Starter #3
Any serious replies?
 

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I know when i first got mine there was a new SMELL to it but i have never seen black smoke. Doesn't sound too good honestly. Doesn't sound like it's the exhaust itself but if youhave the means maybe try to run the stock exhaust for a bit and see what happens.
 

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Discussion Starter #5
RIS300 said:
I know when i first got mine there was a new SMELL to it but i have never seen black smoke. Doesn't sound too good honestly. Doesn't sound like it's the exhaust itself but if youhave the means maybe try to run the stock exhaust for a bit and see what happens.
Yeah, I wasn't too thrilled about it when I saw it. I know black smoke is usually burning oil, but I'm not convinced that is what this is.

Just to clarify, when I say smoke I'm not talking big puffs of smoke, or even enough that the person behind me on the highway would see anything. But if you're standing at the tailpipe when the car is not moving, and you look at the exhaust while someone revs the engine, you will see a black emission in the high rpms.
 

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Mr. Negative
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white smoke is oil. black smoke is generally unburnt fuel. Do you have a CEL?
 

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Correct me if I'm wrong but I thought it was,
white smoke= water mixed w/ fuel, blown head gasket ect.
blue smoke= burning oil
Black smoke= running too rich
 

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Like IS dude said, either unburnt fuel, you're a bit rich, not uncommon, or you could just be blowing some carbon buildup out of the exhaust.
 

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Mr. Negative
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You are correct. I mis-wrote that white was oil. it's water w/ oil. blue is oil.

deftones said:
Correct me if I'm wrong but I thought it was,
white smoke= water mixed w/ fuel, blown head gasket ect.
blue smoke= burning oil
Black smoke= running too rich
 

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You should not rev your engine past 4K RPM under no load, it is not good for the engine.

The little puffs of smoke you see at the upper RPM range under no load is normal. It is due to unburnt fuel when you tip-in under no load more than once in a row.
 

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Swift Racing Technologies said:
You should not rev your engine past 4K RPM under no load, it is not good for the engine.
this this to doublins. :lol: :lol:
 

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Discussion Starter #13
Thanks for all the responses guys... I have no CEL, and no aftermarket intake whatsoever. Nothing hooked up to the ECU. The only engine-related mods I've done is the TRD drop-in filter and the L-Tuned exhaust, so should I still be running rich? Is it common to come from the factory that way?

My guess is it's probably just carbon build up... :-?
 
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