Big black smoky problem

[bacarl]

So this is a new one AFAIK. Kinda a long story...

I ran an autox yesterday (my second event with the MS3) that consisted of four runs. I was doing hot laps, but the car was feeling great and the tires were gripping so I was letting her rip.

On the third run I did a clean launch, grabbed second gear and headed into the first corner, and noticed a HUGE cloud of black smoke drifting away from the starting gate where I'd just come from. I took a break and asked the guys watching if that had only happened that one time and they said yes. I waited a bit and did my fourth run and again got black smoke at launch, but not as bad as the first time. The guy running the start light thought it occured as I shifted into second and got back on the power. He also thought it seemed like oil smoke, although it looked like fuel smoke in my mirror. He also said it had happened to some extent on all of my runs. I had buddies working corners elsewhere on the course and they said it was clean through the slaloms and other turns, only bad at the start.

Back in the pits I was looking things over and found the oil level was high. At the last change I put in exactly 6 qts and checked the level so I have no idea why it would be overfilled. Maybe too much oil was still up in the engine when I checked the level. I also added a spin-on filter at the last change so that increases the capacity if anything.

The only other time I've seen any smoke was one afternoon when I started the car to leave work, it kinda stumbled when it started and I saw a little poof of black smoke out the rear window. I figured that was just richness smoke from the hiccup at idle.

Has this happened to anyone before? I'm kinda stumped and so were a lot of folks at the autox. If the oil is overfilled could it have been forced into the combustion chamber and burned? Does this mean I've had excessive oil pressure since that oil change (2000 miles)? My only mod is Cobb's intake, and it was purchased around December 2007 so it should be old enough that it was made properly - no issues with the air straighener. The fins look nice and straight to me.

I need some help with this!

 

[evilmonkeyMSP]

turbo seals maybe?

 

[ChrisK]

Turbo seals should be white/blueish smoke.

Black is fuel.

bacarl, when you say alot of smoke, do you mean like one big puff, enough to see through the back glass?

I use to get a black puff on take off before I installed a downpipe.
I don't think there is anything wrong to be honest.

These cars just run pig rich.

 

[FrequentFlyer]

Supposedly these cars are ULEV. I just don't see it. When I've got an 1/16th inch of soot on the back of my bumper every week, I don't know how they claim this car runs that clean. I can see some smoke out the back of my car when I step on it sometimes at night as car's headlights shine through it. Can't really see it during the day. Of course, I've seen this happen on my S2000 and RSX Type S when I had them also.

 

[john blutarski]

I find that 5.6-5.7 takes it to the full mark for me. Maybe its just that combined with how rich the car runs from the factory.

 

[john blutarski]

Supposedly these cars are ULEV. I just don't see it. When I've got an 1/16th inch of soot on the back of my bumper every week, I don't know how they claim this car runs that clean. I can see some smoke out the back of my car when I step on it sometimes at night as car's headlights shine through it. Can't really see it during the day. Of course, I've seen this happen on my S2000 and RSX Type S when I had them also.

Somehow I think they are staying out of boost for that ULEV test...

 

[FrequentFlyer]

Somehow I think they are staying out of boost for that ULEV test...

Most likely. Must be at high vacuum cruise for sure.

 

[bacarl]

Turbo seals should be white/blueish smoke.

Black is fuel.

bacarl, when you say alot of smoke, do you mean like one big puff, enough to see through the back glass?

I use to get a black puff on take off before I installed a downpipe.
I don't think there is anything wrong to be honest.

These cars just run pig rich.

I agree about the black being fuel smoke, that's what it looked like to me too. But I just saw it from a distance in my side mirror so I didn't get a close look at all. The guy at the starting gate who was all but enveloped by it thought it seemed like oil smoke. And when I say this was a lot of smoke, I mean like a cloud that looked huge even in a tiny mirror from at least 75 feet away. Like enough smoke to fill your living room.

The other time I mentioned, when I saw smoke at my work, it was a small puff that I saw drifting away through my back window.

 

[bacarl]

I think the overfilled oil scenario is out the window. I changed it last night and got exactly six quarts out. I checked the dip stick after each quart I added to make sure everything was right, and it was. It was right at the Min line after the fifth quart, and right up near Max after the sixth.

So I took six quarts out, then put six back in and was right where I should be. Which makes me even more confused about why it looked overfilled at the autox, but at least I don't have to worry about excessive oil pressure over the last several months.

 

[TonyMS3]

I have never seen a MS3 that didn't puff black smoke when you stomped on the gas. It's fine, don't worry about it. It's annoying, but they run extra rich to prevent possible lean conditions and lower combustion temperatures.

 

[audiosaurus]

More on the smoke

Hi guys.

I've got the smoke, too. Usually happens to me when I'm on the freeway and either drop back a gear to pass or just punch it in sixth. I often get a little hesitation, and I think the smoke I'm getting is blueish, but it happens so rarely I'm not sure about it. Lots of smoke, as bacarl describes.

I can tell you that six quarts is too much, and that if you fill it to the to the line on the dipstick, drive it a little, then let it settle, it will be overfilled. I usually fill it to about the 1/3 to 1/2 way full mark. Then it'll settle down to the full mark on the dipstick. Why? Who knows.

Mine is a 2007 GT, no mods.

If anyone has any more good ideas about the occasional blue or black smoke at high throttle, I'd love to hear it. I'm worried the mill is gonna explode right after the warranty expires....

 

[lasermp5]

does it look like this?

 

[Saitech]

I have had one instance of a quick puff of black smoke while in 6th on the highway. I autoxed this car almost every weekend in the spring/summer and didn't have any issues with black smoke (including back to back fun runs). I put in 6qt every time like you, though I didn't check the dipstick during autox, I'll try to remember to do that next time.

I have similar mods, just a CAI. See if it happens next time. Next local autox is at belle isle on oct 12th, I'll get a video of your run if you want to see it first hand.

Found a vid of someone with the smoke, ms cai+cbe. Check at -31 sec. http://smg.photobucket.com/albums/v...ls/?action=view&current=MazdaspeedExhaust.flv

 

[bacarl]

Thanks man! Yeah that looks similar to what I saw smokewise. Maybe not quite as thick and lingering as mine, but from talking to people that's kinda been the concensus: the car just wanted a ton of fuel right then. That's crazy, I know the cal is rich but that smoke was incredible.

There's an open track day at Waterford Hills on the 12th that I may go to in lieu of the Belle Isle autox. There's a CCM autox at the Cadillac plant on the 5th, then the two Belle Isle events on the 12th and 26th. I'll probably be at at least two out of three, but the gf is already bent out of shape that I have most of the weekends in Oct slated for racing...

 

[bacarl]

Oh btw, if we ever find ourselves at the same event, I would love to check out how your car rides. You've got some Cobb bits, right? Springs and/or sways?

 

[Saitech]

I have cobb springs and sways, a pretty big improvement from stock. Car feels much more planted. I am planning on being at belle isle on the 19th too, Detroit scca is having their last event there. Should be a good month.