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liquidish / carbonish coming from the tailpipe?

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Old 12-23-2009, 06:24 PM
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choinga
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Default liquidish / carbonish coming from the tailpipe?

I'm betting this is fairly common but I thought I'd see where other folks are on this one...

I changed my oil today and when I had the car in the garage warming up before I drained I noticed that, as usual, some liquidy carbonish spray would come out the tailpipe. Even after I changed the oil and let the car get to full warm temp and 14.7 on the wideband, there's still a light spray of this combo coming out of the tailpipe.

I've got various spots of it in my garage and driveway where I've let the car idle at various points over the past year. The car runs/idles/drives fine so I'm not trying to track anything down - just curious if this is common with these cars.

Thanks!
Old 12-23-2009, 06:31 PM
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KuHL 951
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Whatever is making your car run rich at all temps is the cause. My 951 used to spit real bad until I replaced a bad 02 sensor, cleaned the injectors, and finally found the AFM door wasn't closing completely. Your ISV could be sticky also and need cleaning. The moisture is just from the humidity.
Old 12-23-2009, 06:35 PM
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choinga
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thanks KuHL. I've replaced all of those things recently...as in the last several months. I have a MAF, so the AFM door thing is not an issue and it came with new 83#'rs so I doubt dirty injectors are are the problem. But, it's a new O2 sensor that I changed when I was doing the wideband and the ISV is brand new as well.

If my wideband shows 14.7 at warm idle how is the car running so rich? What am I missing?

I'm about to have to take it in to get it inspected so this is really the only reason it worries me.
Old 12-23-2009, 06:41 PM
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KuHL 951
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Originally Posted by choinga
thanks KuHL. I've replaced all of those things recently...as in the last several months. I have a MAF, so the AFM door thing is not an issue and it came with new 83#'rs so I doubt dirty injectors are are the problem. But, it's a new O2 sensor that I changed when I was doing the wideband and the ISV is brand new as well.

If my wideband shows 14.7 at warm idle how is the car running so rich? What am I missing?

I'm about to have to take it in to get it inspected so this is really the only reason it worries me.
Sounds like you have done most everything except maybe the DME temp sensor. If you are spitting that black soot/water that sticks to the garage floor I doubt you can pass HC and CO if it's anything like California. Mine was so far out I was flagged before the end of the test but I could smell mine. Even a new cat won't fix a rich condition. Do you still blow some water after it's warmed up?
Old 12-23-2009, 07:04 PM
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choinga
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haha - I did the temp sensor as well with all of the other stuff - it's brand new.

TX isn't near as stringent as CA and I can't remember if it was pukin' that stuff a year ago when I had to get it inspected after I got it down here. When it's fully warmed up and after a drive it's not near as bad but a little still comes out. I'd have to check again to see for sure and obviously I'd take the car in to get inspected after a few spirited runs to make sure the engine was nice and hot. Either way, still can't figure out why my wideband shows 14.7 but it's apparently still rich?
Old 12-23-2009, 07:18 PM
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fwb42
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Are you running it long enough to get your exhaust system good and hot. Just sounds like built up condensation that needs to be burnt off.
Old 12-23-2009, 07:22 PM
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choinga
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yeah...i need to check it again after a good drive...I just can't remember if it's as bad, although I doubt it. I'll report back...
Old 12-23-2009, 10:15 PM
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944Ross
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Cat converters seem to make this worse than older cars. It's just soot and condensation. Pretty normal in cold weather. There's a pool of it in the end of my muffler tip, I was thinking just today of drilling a hole to drain it.
Old 12-23-2009, 10:17 PM
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I can't help. But, I love you avatar choinga. Haha. Freaking Nascar. Lol.
Old 12-23-2009, 10:41 PM
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Originally Posted by 944Ross
Cat converters seem to make this worse than older cars. It's just soot and condensation. Pretty normal in cold weather. There's a pool of it in the end of my muffler tip, I was thinking just today of drilling a hole to drain it.
3" SFR exhaust with cat-delete on my car, so it's definitely not a cat issue...

Last edited by choinga; 12-23-2009 at 11:24 PM.



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