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[Z06] Running rich?

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Old Feb 7, 2013 | 12:57 PM
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Default Running rich?

I think my z is running rich because the back bumper gets covered in black stuff all the time. The car has a blackwing filter, long tubes, converters, and b&b catback. I assume the car has been tuned because there is no check engines lights, codes ect. What do you guys think? It's there any way to tell if its to rich other than taking it to a tuner?
Here is a video of the car on dyno day. Just seems to have some black smoke that could indicate a rich setting as well. Anyone with more knowledge out there have an opinion?


http://i1214.photobucket.com/albums/...52C7F42C9A.mp4

Last edited by Gmzo6; Feb 7, 2013 at 01:17 PM. Reason: Video
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Old Feb 7, 2013 | 01:11 PM
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Originally Posted by Gmzo6
I think my z is running rich because the back bumper gets covered in black stuff all the time. The car has a blackwing filter, long tubes, converters, and b&b catback. I assume the car has been tuned because there is no check engines lights, codes ect. What do you guys think? It's there any way to tell if its to rich other than taking it to a tuner?
Is it coming from the two inside pipes??
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Old Feb 7, 2013 | 01:15 PM
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No, this car only has two pipes out the back. B&b catback
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Old Feb 7, 2013 | 01:23 PM
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Originally Posted by Gmzo6
I think my z is running rich because the back bumper gets covered in black stuff all the time.
Either you're burning oil or you have a bad tune. Check your oil level now, and in another 500-1000 miles. If it reads the same both times, then you need a new tune. That's my opinion, at least.
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Old Feb 7, 2013 | 01:26 PM
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doesn't burn hardly any oil. It is an 01 and they're known to burn a little but nothing crazy. I would guess I add 1/2 a quart a month, which I think is normal considering it does see high rpm's sometimes. So I'm leaning toward a crappy tune. I bought the car already modded so don't know a whole lot about its past.
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Old Feb 7, 2013 | 01:29 PM
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Another thing - the first tune I had was overly rich. At the end of a drive, after shutting off the engine and exiting the car, I would smell gas every time. That seems like a sure-fire way of knowing you're rich (although it's probably not a necessary requirement).
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Old Feb 7, 2013 | 01:31 PM
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I wonder if it has anything to do with the o2 sensors or converters? I remember when I first bought the car it seemed low on power and I got on it hard and it blew a bunch of black stuff out the back and ran strong after that. Could the converters be stopped up?
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Old Feb 7, 2013 | 01:34 PM
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Originally Posted by Gmzo6
No, this car only has two pipes out the back. B&b catback
This time of the year (cold ) it will run lean
I have black inside both of my inner pipes
It's common , if have a large amount if carbon build up
I'm not sure ...
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Old Feb 7, 2013 | 01:40 PM
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Originally Posted by James2002z06
This time of the year (cold ) it will run lean
A properly dialed-in tune will have leeway to account for differences in temp/humidity, no?
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Old Feb 7, 2013 | 01:54 PM
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Originally Posted by skyavonee
A properly dialed-in tune will have leeway to account for differences in temp/humidity, no?
According to the shop that tuned mine , infact I took it back in about a month ago anyway he told be that it was normal for it to run a little lean this time of year , so to answer your question it would be yes
This was a pretty hot topic a few weeks ago on the forum
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Old Feb 7, 2013 | 11:01 PM
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If you had it dyno'd, you should be able to see what the air/fuel ratio was during the run.
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Old Feb 7, 2013 | 11:03 PM
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well a smart person would of asked or looked. I just stood back and recorded it with asking
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Old Feb 7, 2013 | 11:21 PM
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Usually your WOT AFR is on the dyno sheet they give you. Another possibility is do you floor it all day, every day? Even a cleanly tuned car will be a little dirty at WOT, just the nature of the beast. In my limited experience though, only a pig rich WOT AFR will make the bumper dirty in short order. Well a pig rich cruising AFR would too, but with no CEL it can't cruise that far off or it'd hit you for exceeding the 20 or 25 percent swing.
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Old Feb 7, 2013 | 11:24 PM
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Ill check the dyno sheet and see if it tells. So are you suggesting it could be something other than tune? Maybe converters, o2's, dirty mass air sensor ect
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Old Feb 7, 2013 | 11:32 PM
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I'm leaning heavily toward the tune myself, seeing how the car is modded and you're not 100% sure if it ever was tuned and even if it was, there's always the possibility that it still sucks. I was just throwing out ideas above.
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Old Feb 7, 2013 | 11:35 PM
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your prob right. For all we know its some bull crap tune. owell when I put a cam in it ill get it retuned and then it should be right.
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Old Feb 8, 2013 | 02:09 AM
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Are you in a closed loop idle or open loop idle?... You really need to have someone look at the tune.. Certain Codes can be programmed out too.. You may have O2 sensor issues as well.. A good tuner will be able to resolve your issues and have your car running to its full potential. It will be money well spent.. Good luck
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Old Feb 8, 2013 | 02:36 PM
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Black stuff on your rear bumper is common on our car's.
A Oil catch can will help reduce it, but not eliminate it.

My understanding of the issue:
1.) Your pass side valve cover has a black rubber line running into your throttle body. Oil vapor will get into your intake manifold, and when it gets burned in your combustion chamber it will spew out some black crap out the mufflers.
2.) Your engine valley pan also has a line connected to it that goes into your intake manifold. There is also some oil vapor that will get into your manifold and burn in your combustion chamber that will show up as black crap out the mufflers. My black catch can in my pic (just in front of the pass side head) has helped cut down on the black crap, but not eliminated it.

Before my catch can was installed i had Silver Dollar sized "pools" of oil inside my intake manifold. After the catch can install the inside of my intake manifold was just "glossy" looking. No more pools of oil.



You can see the black hose running from the pass side valve cover to the throttle body. You can also see my oil catch can in front of my passenger side head.




Oil Catch can connections. From the valley pan to the intake manifold. Helps keep oil from reaching my intake manifold.




Hope this helps
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Old Feb 8, 2013 | 02:43 PM
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I have a catch can. It did help some but I still think its a bad tune or converters, o2 sensors
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Old Feb 8, 2013 | 02:47 PM
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Originally Posted by Gmzo6
I have a catch can. It did help some but I still think its a bad tune or converters, o2 sensors
It could still be ... yes.
Have you taken a look inside your intake manifold ?
Does not take long to pull off the flex hose in front of your TB and use a flash light to look inside your intake manifold. See if you can see any pools of oil. Just a thought.

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