first off i have an 03 gmc 4.8 with intake, flowmaster, and superchips. just rolled over 110,000 the other day.
yesterday my friend was following me home and he said that when i floored it, there was a stream of grey/black smoke until i let off. i have heard of the these motors smoking but the ones i have seen have closer to 200,000 miles on them. i figure it is just blowby from a high milage engine, but was curious to know if any of ya'll have had this happen.
MY GARAGE - http://www.ls1truck.com/forums/my-ga...ns-garage.html
2004 GMC Sierra - RCSB
Maybe it is unburnt fuel because the superchips is making you run way fat and youve never noticed it before.
2000 Silverado ECSB- 5.3 CAI, Pacesetter LTs, ORY- Pipe, Magnaflow XL, E-fan, Ported T/B , Nelson Tuned, Built 4l60e, Circle D Stall, 3.42s G80, 2-4 Drop, Hertz Highs, Rockford 501s
2004 Buell XB12s
Originally Posted by LamboDoNoMo
maybe, but surely someone else would've told me in the past 3 years, it was smoking, don't you think.
MY GARAGE - http://www.ls1truck.com/forums/my-ga...ns-garage.html
2004 GMC Sierra - RCSB
Black smoke is usually an indicator of rich mixture.
You may have an injector sticking open.
Has mpg changed lately ?
or poor tune as said before
or MAF not reading right and throwing off air/fuel ratios
You can always do a compression test and leak down test to check
for blow-by. Testers are relatively cheap and a nice tool to have in the box.
Smoke from blow-by and oil leaks will usually appear gray/blue and not black
Last edited by r.barn; 04-24-2009 at 01:57 PM.
2002 Tahoe 4.8 - soon to be turbo'd - SOLD
1989 Mustang - LX Vert - 351W-TT - 2inches of dust covering it
2012 Raptor - 497rwhp at 10psi
If you aint breaking - you aint going fast enough
it dropped from 16.5ish to 15 to 15.5ish since i put the black 17's on, i figure that is because each wheel wieghs about 10 lbs more.
MY GARAGE - http://www.ls1truck.com/forums/my-ga...ns-garage.html
2004 GMC Sierra - RCSB
it could have also been blowing accumulated soot out of you exhaust system, my work van does it, floor it and it blows black soot/smoke, floor again and there's nothing.
Big slow mud truck with a TUNE!!!!!!
it did it everytime i floored it on a 15 mile trip.
MY GARAGE - http://www.ls1truck.com/forums/my-ga...ns-garage.html
2004 GMC Sierra - RCSB
You need to have someone rev up your truck for you so you can see if its gas or oil.
2004 Buell XB12s
my 5.3 had 280,*** on it and started smoking. turns out i lost compression
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