I have smoke coming out my exhaust, not sure if its blue or black, only at WOT, and its very lil and not consistant, should I worry about anything or common for semi-built motors to smoke a lil?


Modified by hondachris1994 at 6:26 PM 1/16/2007

 

yes, you're burning oil. check piston seals and your headgasket.

 

Or valve stem seals

Perform a leakdown test

 

I cant really tell if its blue or black

 

what car/engine?

 

94 civic b16a2

 

Yea if it's blue you're burning oil in 90 percent of the cases. If it's black it's a lot of carbon buildup and that'd mean you're running generally way too rich.

 

get a leakdown test or do one yourself.. that should give you a few more answers than guessing what color the smoke is

 

the car has been street tuned with O2 disabled... Ive never done a leakdown test...what will a leak down tell me and is it pretty simple to do?

 

if your car is running without an 02 sensor then you're probably running too rich and the smoke SHOULD be black but either way smoke is bad and check it out...and if you burn any type of oil or gas in excess then it'll ruin your cat which anyone will tell you is expensive to replace.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mighty_sol &raquo;</TD></TR><TR><TD CLASS="quote">if your car is running without an 02 sensor then you're probably running too rich and the smoke SHOULD be black but either way smoke is bad and check it out...and if you burn any type of oil or gas in excess then it'll ruin your cat which anyone will tell you is expensive to replace. </TD></TR></TABLE>it has a O2 sensor but its been disabled when I got my car tuned, and a cat is cheap $50 for the cat and a sawzza and some welding and its done

 

I was thinkin maybe the smoke was carbon build-up cause its not smokin all the time just sometimes at WOT, mainly around vtec engagement

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jtchinoy &raquo;</TD></TR><TR><TD CLASS="quote">yes, you're burning oil. check piston seals and your headgasket.</TD></TR></TABLE>

what is a piston seal?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Turbo_y8 &raquo;</TD></TR><TR><TD CLASS="quote">

what is a piston seal?</TD></TR></TABLE>I think he means piston rings, my piston rings and pistons were replaced about a year ago with JE pistons and rings

 

yea i fugured that, just being a smart ***

 

hondas usually burn oil from the valve seals. Your motor might have been burning a little earlier as well and you just didnt notice. Or sometimes if a motor sits for a long time, they become brittle. When you start it up, you will cause a valve seal leak. It's very common. Were your valve seals repalced? Did the place that built your motor do a good job of tolerencing? (thats not a word). A leakdown test wont show valve seal wear. Since the shops around here charge $200 to replace valve seals, parts and labor, you may as well do it.

If your rings are not sealing, you're looking at a significant performance drop, gas mixing with oil (rising and falling oil level), and lots of smoke. all depending on how bad your problems are.

Or it may be a little carbon blow out that is normal on all cars. This could come out as either a white-ish blue-ish puff. You see it all the time when cars floor it. The smoke in this case could also be black. Maybe you're running a little rich. Or maybe there's some old carbon inside your exhaust steam. Maybe you're running too rich for your cat, so it cleans some of the exhaust, but it cant clean it all, and it comes out as a carbony (again, thats not a word), bluish whitish, sometimes grayish smoke.


If your headgasket is broke to the point of leaking oil into the cylinders, believe me, you'd know. You'd look like a steam locomotive from all the coolant that would have to dump into your cylinders before you ever got to the oil passages. Plus you'd have ZERO compression in the affected cylinders, and other very nasty things.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B serious &raquo;</TD></TR><TR><TD CLASS="quote">hondas usually burn oil from the valve seals. Your motor might have been burning a little earlier as well and you just didnt notice. Or sometimes if a motor sits for a long time, they become brittle. When you start it up, you will cause a valve seal leak. It's very common. Were your valve seals repalced? Did the place that built your motor do a good job of tolerencing? (thats not a word). A leakdown test wont show valve seal wear. Since the shops around here charge $200 to replace valve seals, parts and labor, you may as well do it.


</TD></TR></TABLE>I had a head job about a yr ago with new valves and valve seals....when valve seals go bad you usually have smoke on start up, which I have no smoke on start up<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B serious &raquo;</TD></TR><TR><TD CLASS="quote">
If your rings are not sealing, you're looking at a significant performance drop, gas mixing with oil (rising and falling oil level), and lots of smoke. all depending on how bad your problems are.
</TD></TR></TABLE>piston and rings were replaced a yr ago also, and its very lil smoke, and not all the time<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B serious &raquo;</TD></TR><TR><TD CLASS="quote">

Or it may be a little carbon blow out that is normal on all cars. This could come out as either a white-ish blue-ish puff. You see it all the time when cars floor it. The smoke in this case could also be black. Maybe you're running a little rich. Or maybe there's some old carbon inside your exhaust steam. Maybe you're running too rich for your cat, so it cleans some of the exhaust, but it cant clean it all, and it comes out as a carbony (again, thats not a word), bluish whitish, sometimes grayish smoke.
</TD></TR></TABLE> The car has been street tune, but it could still be running a lil rich sometimes, or carbon build-up<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B serious &raquo;</TD></TR><TR><TD CLASS="quote">


If your headgasket is broke to the point of leaking oil into the cylinders, believe me, you'd know. You'd look like a steam locomotive from all the coolant that would have to dump into your cylinders before you ever got to the oil passages. Plus you'd have ZERO compression in the affected cylinders, and other very nasty things. </TD></TR></TABLE>definately not the headgasket, cause your rt I would definately know it

 

bump

 

I would check the valve stem seals. I had a problem when I had my car rebuilt upon installing the piston rings the tech installed them and had made a small crack in one of them. I had the same problem as well that sometimes the car would smoke and its would smoke more at high rpm's or if the car was idle and was reving it would smoke.