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picnic_george
August 27th, 2013, 06:18 AM
OK this has been covered a million times. But the typical idle smell is happening.
The cam is not very big, #s are .613/.576 227/234 115, this has very little overlap. When I make idle around 16:1 the smell goes away. But as soon as I set it back to 14.7 or turn on the o2 sensors which switch around 14.7 it gets a little smelly again.

Is this just something that can't be fixed or does it seem like there is a mechanical problem with the car? That cam profile is odd to me so I'm not sure what to think. Stock LS6 with headers exhaust etc.. I won't lose any sleep over it if there is nothing to be looking at.

picnic_george
September 11th, 2013, 04:52 AM
BUMP

The cam had a bunch of advance ground into it which may have had something to do with it. I got it a lot better but the fuel trims don't make me real happy at idle. That car runs and drives great.

But for reference. Is there a trick I'm missing? I have't played with closed loop proportional idle tables, will that help?

5.7ute
September 11th, 2013, 08:47 AM
I found that my best idle stability was around 15.6:1 & kept closed loop turned off around idle. (I use a COS & use semi closed loop) If I allowed trims to be active I would also get the fuel smell & idle quality wasnt great.
Give it what it likes instead of trying to hit a number & you will both be happier..

picnic_george
September 11th, 2013, 09:04 AM
I think that's a great way to do it for a lot of applications. But for MAF enabled CL I don't think that is possible is it?

5.7ute
September 11th, 2013, 09:49 AM
You could lower the O2 switchpoints in the idle areas, which will keep it leaner.
Also you can run a COS & retain the maf.

picnic_george
September 12th, 2013, 01:24 AM
I'll have to look into lowering the switch points in the idle areas. Haven't played with that. Thanks :)

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