Crate

Hey, i was told today that im puffing alittle smoke at high rpm's by a friend who was behind me.. he said it was just alittle black.

And from talking to my friend (good mechanic) he said i'm either running really rich or lean. Cuse its not oil (white smoke) its smoke as in im det'ing.

As some ppl mentioned.. ludes run rich from the factory right? I'm guessing (the previous owner said he has re-grinded cams in) that they cams are either set really rich or really lean... not sure until i get a stoichmeter. I can tell from the plugs right? white buildup its running lean, black buildup its running rich? or the other way around?

Thanks,
Crate

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jdm h22 - 180.3whp 151.4lbs/ft

brendon2k

Your O2 sensor and fuel curve maps determine how much gas to put in the engine. I bet you are running rich.

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-Brendon-
09 - Subaru Impreza
07 - Honda CBR 600RR

VeeTec

If you were on the gas hard, this is normal.

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2007 Honda Odyssey EX-L w/RES (Taffeta White/Ivory Leather) 8 Passenger Family Hauler! *stock*
2009 GTI 4D United Grey Metallic (Black Leather) 6 speed *stock* (For now)
Warren

Crate

i asked a friend who's at a tech school.. he said it sounds like "HydroCarbon Blow-by" ..... aka left over gas. =]

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jdm h22 - 180.3whp 151.4lbs/ft

JDM Lude

you can't set cams too rich or too lean. Fuel curves are determined by the ECU.

A bit of black smoke at high RPM and a puff on an upshift is normal. Preludes do run too rich at high RPM. Replacing the O2 sensor won't do anything, as the ECU ignores the O2 sensor at anything above 30% throttle.

black smoke = running rich
white smoke = your motor is trashed

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Absolut

Mine does the same thing, I get a lil bit of black smoke when im on it real hard.

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Jason

brendon2k

Isn't it at 80% trottle the o2 sensor doesn't determine the amount of fuel injected. Also if your o2 sensor does start to go out your can will start running very rich.

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-Brendon-
09 - Subaru Impreza
07 - Honda CBR 600RR

NirVTEC

I was told before that it was carbon build up in the exhaust system that gets knocked loose when you hit it hard. When I hit it hard, I can see a little puff of smoke behind me. I assume this is only in older cars, I have 95k miles.

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1993 Prelude VTEC(a.k.a. GATOR)13.37@108mph
-JDM H22A(267whp/240tq)*100% TUNED*

1994 Prelude Si(a.k.a. SMURF)
-JDM H22A(187whp/152tq-@LL MoToR)*UNTUNED*

Crate

its not enough that i can even see it. Just my freind noticed it from behind me.

I was behind a older rx7 today.. he floored it and it was a smoke screen. so i dont worry about it.

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jdm h22 - 180.3whp 151.4lbs/ft